Storm Australian Severe Weather Forum

Severe Weather Discussion => Australian Severe Storms, Weather Events and Storm Chasing => Topic started by: James on 19 December 2007, 11:37:50 AM

Title: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: James on 19 December 2007, 11:37:50 AM

Looks to be a fairly nice outbreak of storms ahead for NSW during this period. GFS has some pretty amazing wind speed and shear on the cards although it is still a few days away so it is bound to change. When I say amazing Im talking about a surface ne'r around 10 knots, 20 knot NNE at 900, 25 knot northerly at 800, 31 knot NW'er at 700 with a nice 40 knots at 500 and 70 knot exiting Jet above it. As far as shear goes in Australia this would have to be up there with the best of them. Nice moist layer around 800 with a dry slot above at 650.  But with positives come a whole heap of negatives .... Lapse rates aren't exactly awesome, Instability isnt huge, GFS has DP's of 19 to 22c across inland NSW (I'll believe it when I see it) which could in turn affect the LI's, quite warm at 500 with -9c and then there is that horrible pesky upper level moisture and cloud that seems to be hanging about.

Will be interesting to see what subsequent model runs have in mind with this system. Certainly the wind is there!

James

Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Richary on 19 December 2007, 04:18:53 PM
Certainly the TV weather forecasts for Sydney aren't showing much activity until maybe Friday, probably due to the SE wind we have at the moment. Looking at radars and warnings the southern central area of Qld seems to be getting most of the activity lately.

The storms seem smaller in diameter but still intense out there at times, has anyone ever chased out there to see the structures and so forth?
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Richary on 20 December 2007, 02:32:23 PM
SA seems to have copped it today, with severe damage in the Mallee country around Pinnaroo from the news reports I have just come across. And severe storm warnings over much of SA and western Victoria all the way to Melbourne. Maybe the front will bring something good here when it finally arrives, forecast for Saturday.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Carlos E on 20 December 2007, 03:19:47 PM
I'm in SA and very disappointed with the storms today. I'm pretty sure they hit everywhere in the state except Adelaide.... :(

Friday looks to be a pretty good day for some unstable weather, I'm hoping so.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Richary on 20 December 2007, 04:48:35 PM
Yeah well, in the 5 years I was in Adelaide and lived various places from Glenelg, Ridgehaven, Wynn Vale and Brompton I only remember one really good storm when we were visiting my now (luckily) ex partners brother down near St Peters about this time last year. Awesome lightning all over, and of course I didn't have the camera. All the other storms where I lived there were off in the distance.

Seems you need to be in the right place there to get the storms, and I never was.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Macca on 21 December 2007, 07:50:39 AM
Tomorrow has the potential to be exceptionally potent in Victoria with a rapidly deepening surface feature being overlayed by a strong upper level trough.  GFS *SCREAMS* tornado potential tomorrow.  This is pretty close to the typical (but infrequent) set up required for warm-season tornadoes here in Australia.  I've changed my flight to early tomorrow morning (Bris - Melb) so I can chase in the afternoon.

Just to add to this a bit more...

GFS has a surface low deepening over central Victoria to about 992hpa (strengthening rapidly in response to the strong upper trough pushing up from the SW).  850mb winds are forecast to be 30-35knts from the NNE with surface winds probably being out of the NE in the 15-20knt vicinity.  Atop this with 45-50knts at 700mb and 55-60knts at 500mb and we have some very interesting shear.  Its the type of shear and synoptic set up that has, in the past, resulted in tornadic thunderstorms.  The main problem tomorrow could be too much upper level moisture.  If that can be negated, there should be some pretty awesome storms.  With large areas of thunderstorms across much of Victoria today, there should be plenty of moisture in the lower levels. 

I'm excited!
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Mike on 21 December 2007, 09:26:06 AM
A lot of talk on the weather channels re the severe storms set to enter SA, VIC and lower NSW by Friday and Sat.  Given the wind shear you mentioned Macca it will certainly be a day to have that camera and video set up.  SA and VIC should be the hardest hit.  They reported the high possibility of gusts, hail, flash flooding and dangerous lightning - (mmm.. must mean very frequent flangs!).  There's a lot of warm moist air feeding in and with the cold front moving to the lower southern areas and coasts it will be insane for chasing. 

BoM issued for areas northwest of Adelaide - it's coming!

TOP PRIORITY FOR IMMEDIATE BROADCAST
SEVERE THUNDERSTORM WARNING
for DAMAGING WIND and FLASH FLOODING
For people in the Northwest Pastoral and parts of the West Coast districts.

Issued at 2:07 pm Thursday, 20 December 2007.

Severe thunderstorms are likely to produce damaging wind gusts in excess of 90
km/h, very heavy rainfall and flash flooding in the warning area during this
afternoon. Locations which may be affected include Marla, Coober Pedy, Ernabella
and Tarcoola.



Good luck fellas :)

Mike
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Michael Bath on 21 December 2007, 11:31:01 AM
Two very impressive cells in Northern Vic and Southern NSW at present. Echuca and Deniliquin in the firing line

VIS at 5pm

Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: James on 21 December 2007, 01:09:28 PM
I really hope someone is out there chasing either one of those two storms near the Vic/Nsw border. The northern one near Deniliquin is looking really nice on radar. Absolutely brilliant chasing country out there too with flat open plains and not too many trees!

Just a couple of interesting observations I have noted with the radar of these two cells. The Deniliquin storm developed at 1400 near Gredgwin in Victoria moving in an Easterly direction until around 1550 it starts it's move left near Pyramid Hill. From 1550 till now (1850) it has moved NNE around 130kms. Another interesting radar feature is the cell north of Deniliquin at 1700 starts a rapid move south towards the Supercell moving north. It gets eaten up just east of Deniliquin at around 1800. Im interested why the rapid move south for the hour before hand. Did it has something to do with the supercell 'sucking in' the winds to the north towards it. I would not have thought so considering steering winds are around 700 to 500.

Another interesting feature is just how good the inflow was for this cell. Comparing Radar to Observations in town the 30 minutes prior to the storm had surface winds from the E gusting at 39km/h with a NE gust at 534pm of 48km/h. Considering that radar had the precipitation crossing town at between 530pm and 540pm I would be estimating that the 48km/h gust was just prior to the precip curtain hitting. Looks to me the inflow is strong enough to keep the outflow from pushing out and dominating. That doesnt happen very often. 10 minutes later, and well and truly under precipitation,  the outflow hits 108km/h from the south. Impressive!

A very interesting storm that I hope we get to see pictures of shortly!

Possibly more to come tomorrow.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jane Gough on 21 December 2007, 01:41:21 PM
Melbourne December 20th 2007

A very interesting afternoon experienced in Melbourne today with some very impressive 'greenage' photographed before the storm unleashed it's fury. Photos will be posted eventually...I'm still processing flood images from December 3rd!

I left my vantage point just in time before we received approximately 56mm in an hour, falling at a record breaking 261mm/h on my weather station. My garden and driveway were completely under water, and we had at least 20 litres of water caught in buckets pouring through the meals area window and onto the floor (the window was shut at the time...). The gutters simply couldn't cope. Mixed in the rain during the height of the storm was approx 2cm hail (I was not going to risk my life and venture out with a pair of calipers!), and it certainly didn't hang around too long on the ground either. Plenty of close lightning and wind gusts. Difficult to take pics or video while trying to comfort distressed children and help hold a bucket up to the waterfall coming down the wall!!

All quiet now and the sun is beginning to push through the clouds. I will have pics and report online soon after Christmas...things are just a little busy!
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Peter J on 21 December 2007, 02:06:24 PM
Hi All,
As one who lives and works in the outer-eastern part of Melbourne, I don't think I have witnessed live a rain event as intense, in a smallish area, like we had in Melbourne this afternoon for at least 17 years. From around 2.30pm the weather had started to build up in the western sky, as I observed from my vantage point in Nunawading. By the time I had reached my last drop-off point for the school bus run (around 4.35pm), the storm had turned quite dark across Glen Waverley, and south west of the main gust front, the weather was a startling silver white as the heavy rains arrived.

When I looked to the west at this point I noticed the sky had a greenish hue about it, and was expecting to see some hail. What followed was torrential. Travelling west along Burwood Hwy, Vermont south was like driving a boat along a strong river current. The northern (right hand) lane was at least a foot under water, and driving a school bus was treacherous. What was more amazing was travelling north along Terrara Rd and Rooks Rd in Vermont - Terrara Rd was like a river torrent, at least 1.5 foot deep, and made driving really hard. I was struggling to change gears on the bus without the bus slipping in the water. I got the bus to Canterbury Rd, turned right into Rooks Rd, travelled just 100m, and had to turn around as the road was submerged in 2 foot of water, and two cars had become engulfed to the windows, and couldn't move.

Even though the rain gauges said we only got 36mls for the day (to 6pm), I was sure the area where i was got close to 80mls in 1.5 hrs.
Very Intense and very scarey driving.

Hope I didn't bore anyone. Oh and the lightning (quite a few CGs - very silver in colour) was spectacular.

I don't get to see many rain/storm events here, but they are worth mentioning when they do happen.

All the best for Christmas, everyone.

Peter J
amateur weather observer.

Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Ewan on 21 December 2007, 03:18:48 PM
Hi everyone

My first post though I have been reading the forum for a little while. I am a total novice and dont always understand the terms but anyway I will keep reading !

the storm this afternoon in Melbourne was really unlike any I have seen here for a very long time. I took some shots from the top of Box Hill Shopping Centre ( just a lousy digital I'm afraid) but it shows the striking black and aqua/green colour in the clouds just before it dumped an amazing amount of water on us. No hail but a lot of wind gusts that I observed to be alternating between east and southwest.
Apologies in advance if I havent uploaded the pic correctly - I'm getting the hang of it!

I noticed a lot of small rotations in the clouds. Did anyone else see this?

(http://i174.photobucket.com/albums/w100/BellarineRecordings/100_5794.jpg)
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Richary on 21 December 2007, 03:37:55 PM
The Melbourne storms certainly looked impressive on the radar and thanks to all those people who have posted pics and stories from there.

Going back to the SA storms yesterday, the news report was interesting about the cause of the damage - pics at this link. http://www.news.com.au/adelaidenow/large-gallery/0,25543,5028374-5014156-1,00.html

This story has the bureau's explanation.
http://www.news.com.au/adelaidenow/story/0,22606,22949065-2682,00.html

THE terrifying wind storm that lashed the state's Mallee yesterday was not a genuine tornado, the Bureau of Meteorology said this afternoon.

Despite widespread speculation that the small Mallee town had experienced a rare giant funnel of wind - or mini tornado -  the bureau this afternoon said the freak weather was most likely caused by an excessive "down draught" from the heavy rain clouds.

As winds gusted up to 90km/h, the State Emergency Service received 15 reports of building damage at Pinnaroo.

This included the hospital, where three trees were uprooted and an air conditioning unit was dislodged, and two Devon Tce homes expected to require demolition.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jane Gough on 21 December 2007, 05:50:42 PM
Here are a couple of pics of the Melbourne storm this afternoon. They were all taken from Chadstone looking south. No colour adjustments at all with these images

(http://www.stormygirl.net/images1/green1201207.jpg)

(http://www.stormygirl.net/images1/green2201207.jpg)

...and a link to a quickly stitched together pan showing nice structure...for Melbourne! (144kb)

http://www.stormygirl.net/images1/greenpan1201207.jpg
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Mike on 21 December 2007, 08:55:14 PM
Nice reports/photos there from everyone.  :)

Welcome to Ewan who typed in his very first post, well done !  Don't worry about the terminology - you'll get the hang of it and if you browse the forum you'll see all sorts of threads relating to all sorts of weather language.  Ask anything you like - we're all fairly patient, really!

Look forward to more on this supercell and the related images.

Mike
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: David Brodrick on 22 December 2007, 04:01:24 AM
Flash Flooding at St George

The BOMs weather station at St George recorded 82mm last night and gusts to almost 80km/h before the anemometer broke.

However some bloke reports he had 108mm in half an hour and then another 20mm later on. Here is the ABC News article:
http://www.abc.net.au/news/stories/2007/12/21/2124811.htm

Severe storm floods streets, causes 'chaos'

A severe thunderstorm has lashed the southern inland Queensland town of Saint George, flooding streets, houses and a pharmacy, and bringing down trees and power lines.

The Queensland Fire and Rescue Service says it received a number of calls for help.

Resident Roy Aldridge says 108 millimetres fell at his house in half an hour, and there was another 20 millimetres later in the night.

Mr Aldridge says the water was knee-deep across roads, and the wind caused chaos.

"It was interesting to see people try to negotiate the southern end of Scott Street through all the limbs and branches," he said.

"Further down the street there's a house with a large jacaranda just blown to pieces."
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Shaun Galman on 22 December 2007, 06:19:27 AM
Hi guys,

Good to see some great reports from VIC after all the amazing storm action here in NSW!

Flash Flooding at St George

The BOMs weather station at St George recorded 82mm last night and gusts to almost 80km/h before the anemometer broke.
I can understand these claims David. We had three HP cells come through our area yesterday evening also. The first built to our north around 3pm and came across the western edge of town. This cell had a nice dark base on the leading edge, a nasty rain core and was fairly active.
The second cell came in directly across town from the north west at 4:37pm with alot more rain ferocity and was carrying a nice inflow shelf (I managed a couple shots from my roof quickly before the deluge). This storm wasn't as active as the first, only some minor intra-cloud light. It looked very dark and impressive upon approach.
The third cell and most severe rolled in directly behind the second around 6pm and let loose with a ridiculous barrage of CG throughout town! We heard one pretty close strike that lit up the house (even with the blinds drawn) and made us jump with the resulting CRACK of thunder! I would've guessed this strike was anywhere within a hundred metres? The rain was torrential to say the least and the totals for the three storms came in at 38mm.

It's the first time that I couldn't manage any sort of lightning photography at all due to the constant heavy rain, this is an extreme rarity for me as I will usually try anything for a good photo? Just a little too dangerous, unpredictable and wet this time!

Cheers guys,
Shauno 
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Carlos E on 22 December 2007, 11:26:33 AM
Had a pretty noisy storm in terms of thunder this morning in Adelaide.

Some notes about today thus far:

Gusts of 120km/h at Broken Hill;
Gusts of 120km/h at Coober Pedy;
Gusts of 105km/h at Wilcannia.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Shaun Galman on 22 December 2007, 11:40:13 AM
Hi all,
Just got back from a chase..not alot of photos...storms were inbound at 80km/hr so some nice approach shots, but after that just heavy rain and isolated embedded storms....so humid Id swear it was singapore. Will post some pics shortly
John: I cant stress how much I agree with you about the tropical feeling to the weather! I think they need to move the tropics line further south to cover all of us in the SE! ;)

21 December 2007. Upper Western NSW Storm Update & Photo
I just took a few shots of yet another HP cell, and like John, a few nice approach shots but no actual substance to the storms. This storm broke the cap around 4:30pm and came across the Ridge just to the north at 5:15pm when I shot the small panorama below. I heard a few rumblings but didn't actually catch any CG, but they would surely be out there. Also in the shot below you will notice the build line in the distance. These storms are on the approach now so I will keep an eye out in the coming hours :)
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1763&g2_serialNumber=1)

Cheers guys,
Shauno
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Michael Bath on 22 December 2007, 01:13:08 PM
This was aired on Channel Seven this evening. A tornado was reported near Ballarat, VIC 20th Dec 2007. Really need to see much more of the clip to see what is going on. Seven didn't show enough and had their stupid logo all over it.

---> Video Clip (http://australiasevereweather.com/video/movies/2007/1220tv01.wmv) < ---


(http://australiasevereweather.com/video/stills/2007/1220tv01.jpg)

(http://australiasevereweather.com/video/stills/2007/1220tv02.jpg)

(http://australiasevereweather.com/video/stills/2007/1220tv03.jpg)

(http://australiasevereweather.com/video/stills/2007/1220tv04.jpg)


Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jeff Brislane on 22 December 2007, 01:55:33 PM
MB, I saw the same footage tonight and the voice on the camera sounded kind of like that guy who had the website stormplanet whatever his name was. It also looked remakably like a tornado from the past that occured near Booloroo in South Australia. can you get some radar up of the storm?

Jeff.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Michael Bath on 22 December 2007, 02:16:59 PM
Interesting cell to your east now Shauno - hope you get a show from that or that later stuff still moving in from the SW.

Some nice falls about again in Melbourne - thanks for reporting that John. Hopefully many sites have picked up some great totals.

Jeff - the footage is by Clyve Herbert - I assume taken looking at the cell which passes south of Ballarat.

Some data for the event

---> Melbourne 128km radar loop (http://australiasevereweather.com/storm_news/2007/radar/20071220/melbourne128.htm)


(http://australiasevereweather.com/storm_news/2007/thumbs/2007122000melbourne.png) (http://australiasevereweather.com/storm_news/2007/soundings/2007122000melbourne.png) Melbourne 00z


GFS analysis Thursday 20/12/2007 06z

Instability: CAPE (http://australiasevereweather.com/storm_news/2007/maps/2007122006cape.png) / Lifted Index (http://australiasevereweather.com/storm_news/2007/maps/2007122006li.png)

Relative Humidity: 0300 (http://australiasevereweather.com/storm_news/2007/maps/2007122006rh0300.png) / 0500 (http://australiasevereweather.com/storm_news/2007/maps/2007122006rh0500.png) / 0600 (http://australiasevereweather.com/storm_news/2007/maps/2007122006rh0600.png) / 0700 (http://australiasevereweather.com/storm_news/2007/maps/2007122006rh0700.png) / 0850 (http://australiasevereweather.com/storm_news/2007/maps/2007122006rh0850.png) / 1000 (http://australiasevereweather.com/storm_news/2007/maps/2007122006rh1000.png)

Temperature: 0300 (http://australiasevereweather.com/storm_news/2007/maps/2007122006tmp0300.png) / 0500 (http://australiasevereweather.com/storm_news/2007/maps/2007122006tmp0500.png) / 0700 (http://australiasevereweather.com/storm_news/2007/maps/2007122006tmp0700.png) /  0850 (http://australiasevereweather.com/storm_news/2007/maps/2007122006tmp0850.png) / 1000 (http://australiasevereweather.com/storm_news/2007/maps/2007122006tmp1000.png)

Winds (knots): 0200 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0200.png) / 0300 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0300.png) / 0500 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0500.png) / 0600 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0600.png) / 0700 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0700.png) / 0850 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0850.png) / 0925 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind0925.png) / 1000 (http://australiasevereweather.com/storm_news/2007/maps/2007122006wind1000.png)

Note the instability over TAS as well on the GFS charts - there were some storms mainly in the northeast of that state.

MB
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 23 December 2007, 01:04:19 AM
Here are some links that may be found interesting:

http://bendigo.yourguide.com.au/articles/1149541.html?src=topstories

Here is the Weatherzone link to the pictures of the tornado

http://forum.weatherzone.com.au/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=17;t=000348;p=11

I wished there were more.

Regards,

Jimmy Deguara
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jeff Brislane on 23 December 2007, 03:19:10 AM

It certainly doesn't strike me from the gfs plots as an enviroment conducive to tornadoes but there could be a number of other factors involved that basic gfs plots don't show. The wind shear is quite linear above 850mb for starters. Also the radar echo is far less impressive than the later echos of the two obvious supercells which moved north into NSW.

Jeff.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jeff Brislane on 23 December 2007, 03:25:40 AM
I just checked out the photos on that other forum. Is it a gustnado? It certainly looks like it developed along the gust front of the cell to me anyway. The cell doesn't look like a regular supercell as such.

Jeff.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 23 December 2007, 03:44:56 AM
Jeff,

I was tending towards gustnado given the feed from the rain and what seems to be the short lived nature. Perhaps vorticity as the storm tended towards outflow dominance.

There is hardly any rotation I can detect on the video. A tornado of that size from a 'mesocyclone' could easily have noticeable rotation from that distance I would think.

Take not of the distance one of the videos was from the Dunoon tornado 26th October 2007. Even from 2km away, rotation and upmotion was easily visible. If any rotation is apparent, can anyone discern whether it is anticyclonic?

Further, is that inflow on the left side of one of the images or is it an extension of the shelf cloud? It is obvious that a shelf cloud passes over in one of the photographs.

Is doppler available from this distance out?  The Bureau according to the article are still checking to see whether it was a tornado.

Comments?

Regards,

Jimmy Deguara
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Shaun Galman on 23 December 2007, 04:51:53 AM
Hi all,
Interesting cell to your east now Shauno - hope you get a show from that or that later stuff still moving in from the SW.

G'day Michael, I took a few shots of the storm line you mentioned around 7:30pm, saw a few bolts here and there but was I mostly impressed with the massive size and height of the structure! I saw it break the cap twice, the first time showed some typical white Pilus then a few minutes on while still rising it seemed to find another cap and show a thick, somewhat dense brownish/grey Pilus (could this be possibly from extremely heavy moisture aloft?) This storm soon became a gust front of sorts with several dense rain cores along it's length, sparking some nice activity.

I found myself out at 3:25am this morning once again getting a few photos of a highly active distant storm to our south west, somewhere near Walgett, possibly 80k's or more away. This storm was so active that it was causing power disruptions from way out there!

I saw the "tornado" on the channel 7 news last night also guys, the wall cloud looked pretty mean and impressive underneath a massive parabolic/lenticular cloud structure! Reminded me of something you'd see from the Texas Panhandle or Oaklahoma! (the state, not the musical? lol) I'd gather these warm, humid conditions coinciding with a cold front from the south would give rise to a few tornado's over the coming weeks, providing this current trend continues?

The rain has certainly set in this morning! It's so dark that it feels like nighttime? Here's a few current numbers for you- Temp- 23.6. Humidity- 66%. Pressure- 989.70mb and steady. Wind - North 1.1kph. Rain since 6am- 31mm.

I'll compile a short report and get a few shots from yesterday evening and early this morning up today at some point.
Cheers from a VERY wet, muddy and surprisingly green Lightning Ridge! :)
Shauno
 
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jeff Brislane on 23 December 2007, 04:57:29 AM
Hey Shaun I can't believe how green lightning ridge is in your photos! I thought it was semi-arid! You have some very impressive cells to your south last night, and that cell you mentioned with the amazing lightning show was probably the one responsible for the massive rainfall totals around the Warrumbungles. Coonamble has topped the rainfall list this morning with a massive 171mm to 9am! And there are several guages that reported over 100mm.

Jeff.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Michael Bath on 23 December 2007, 05:16:04 AM
Given the significance of the other cells on 20th December 2007 here's some radar loops for posterity.

---> Yarrawonga 128km (http://australiasevereweather.com/storm_news/2007/radar/20071220/yarrawonga128.htm) / Yarrawonga 256km (http://australiasevereweather.com/storm_news/2007/radar/20071220/yarrawonga256.htm)


Sure have been some impressive rainfall totals Jeff !   These to 9am 22nd Dec

NORTHWEST SLOPES:
Barraba Tce Blackville  56 Breeza  16 Gunnedah  16
Gunnedah Ap AWS  16 Mullaley  23 Quirindi  11 Tambar Springs  89
Tamworth Ap AWS   4 Weabonga   8 Woolbrook   2

NORTHWEST PLAINS:
Come by Chance  95 Gwabegar  54 Moree Ap AWS   2 Mungindi   4
Narrabri AP AWS   2 Pilliga  43 Walgett Ap AWS  35 Wee Waa   4

CENTRAL WEST SLOPES:
Binnaway 112 Coonabarabran 141 Coonabarabran AWS 116 Cowra Ap  32
Cowra Ap AWS  32 Cowra RS  31 Cudal  27 Cumnock  31
Dubbo Ap AWS  61 Dunedoo  49 Forbes Ap AWS  32 Manildra  22
Mendooran  69 Parkes  19 Parkes AP AWS  34 Tooraweenah 106
Wellington  51

CENTRAL WEST PLAINS:
Condobolin Ap AWS  40 Coonamble 171 Coonamble AP AWS  60
Gilgandra  81 Gulargambone 125 Marra Ck  64 Mudall  47
Narromine  65 Nyngan 102 Peak Hill  31 Trangie AWS  73 Trundle  57
Tullamore  77 Yalgogrin Nth  18
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Shaun Galman on 23 December 2007, 05:22:02 AM
Hey Shaun I can't believe how green lightning ridge is in your photos! I thought it was semi-arid! You have some very impressive cells to your south last night, and that cell you mentioned with the amazing lightning show was probably the one responsible for the massive rainfall totals around the Warrumbungles. Coonamble has topped the rainfall list this morning with a massive 171mm to 9am! And there are several guages that reported over 100mm.

Jeff.
Hi Jeff,
It is great to see it so green out this way! We are definitely semi-arid as you say but you'd never guess it now! My father and a few other long-time locals are saying this is the best summer rain since the 70's -early 80's. I cant recall such a burst of greenery since the last flooding in 1984! Our only trouble now is that to access most of the opal fields you need to cross the dreaded black-soil lakes. Some of these contain black-soil upto and beyond 80feet in depth! We may not  be able to get out to work for weeks?, though there is kind of an upside to that I guess ;)
From the build line I witnessed developing to our north-west yesterday evening I can see why the totals were up into the high 100mm's most places to our south-east!

Cheers,
Shauno
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: David C on 23 December 2007, 08:16:26 AM
Some VERY nice storms down there and what about Victoria for chase country! - but a tornado in that news segment? Again form the brief footage it looks like a 'scudnado' to me - no motion evident at all. The structure looks wrong for a vortex too - what is that gap at cloud base on the right side -- while it might be a case of perspective and could be some condensing cloud jutting out towards the photographer moving in, it all looks very undynamic. There is obviously more footage of the event, and at that distance if there was clear rotation then it then it should be visible, and maybe it was.  As Michael said it would be nice to see more footage.

In fact, what are we even discussing this for. That storm is well within range of a Doppler radar :) Large tornadoes will not go unnoticed from around that part of the world. E-mail Harald Richter and ask him what the radar was showing at the time.
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Michael Bath on 23 December 2007, 08:51:00 AM
David - Harald happened to write this on the Aussie Wx list and it corresponds to the event:


"As those folks watching the "outside world" around 2pm EDT today will have noticed,
it is rare for Victoria to achieve a juxtaposition of decent deep layer shear
and rich, deep surface moisture.  Today is an exception.
                                                                                                                               
The storms extending from Aireys Inlet to E of Skipton, however, seem to have trouble
capitalising on the deep layer shear.  Their rotational signatures are shallow and
sporadic, something I have seen a few times now with Australia's southern storms.  Maybe the
competition for "the juice" and/or the localised disruption of the wind field
by neighbouring storms is to blame.  The tail end (northern) leftmover E of Skipton
should be least affected by such competition, as evidenced in its longevity
and propagation characteristics.
                                                                                                                               
As of 3:30z we have the northern tailend storm splitting with the leftmover
quickly dominating (nice TBSS - a sign for large hail).
                                                                                                                               
On the previous scan (3:24z), the southern neighbour sported a hook echo and
low-level (< 1000m) mesocyclone - both very shortlived, though."
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 23 December 2007, 09:58:18 AM
Hi Michael,

Is there any other indication as to whether Harold has dismissed this tornado based on doppler and radar characteristics?

Rotation sufficient to cause tornadoes is definitely noticeable from a few kilometres away. I did see only slight shelf cloud shear if any - not sufficient for a 'large tornado'. It is claimed that the tornado became rainwrapped. I would not mind seeing the 11 minutes of footage of this event.

There was a funnel cloud and then outflow is evident given the scud at the base.

Regards,

Jimmy Deguara
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Shaun Galman on 23 December 2007, 12:31:38 PM
Hi guys,
Hers a couple storm images from the 12st Dec. and a couple flooding photos from 22nd Dec. to "wet" your appetite lol ;)
21 December 2007 Upper Western. Storm Photos
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1770&g2_serialNumber=1)
Here's that impressive looking storm line you noticed Michael. This is looking north-west from town at 7:27pm. This is the beast that seemingly broke the cap twice. If only the shear was stronger we may have had a different outcome!
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1774&g2_serialNumber=2)
This is the western edge of the rain cores that formed from the storms in the panorama above. Taken at 8:18pm facing west from 3k's east of town.
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1777&g2_serialNumber=2)
Same camera position as above only looking east. It's funny, I was caught in a major dust storm on these plains just two weeks ago!

22 December 2007 Upper Western. Flooding Photos
Now for some flood shots from this morning! (22nd Dec.)
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1780&g2_serialNumber=2)
This the Castlereagh Highway turnoff to the Ridge. 5k's from town.
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1783&g2_serialNumber=2)
The entrance to town. If we get another inch or two in the coming days, the roads will be surely cut as the ground is pretty well super saturated!
(http://www.ridgelightning.com/gallery2/main.php?g2_view=core.DownloadItem&g2_itemId=1786&g2_serialNumber=2)
This shot speaks for itself! This is typical of the surrounding plains in any direction!
Cheers guys,
Shauno
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Michael Bath on 23 December 2007, 01:31:40 PM
Is there any other indication as to whether Harold has dismissed this tornado based on doppler and radar characteristics?

No - there have been no further comments that I have come across - perhaps you or David can email him ?   

Also - we now finally have some more info about what was taking place. Clyve's tornado was just before 4pm, not earlier as initially thought (why it has taken 2 days to get details is beyond me), so it is part of the line of cells on radar around 05z.  (I have extended the radar loop (http://C:\websites\asw\storm_news\2007\radar\20071220\melbourne128.htm))

Another observer, Andre Dalton took these photos are wrote:

"I was on Thompsons Rd, about 10 ks south of Beaufort, with a mate from work - Matt Carey (Tech Officer)- saw two lowerings - the one at the far rear flank of the storm became a large wall cloud, then just dropped it.....it started feeding off the other lowering, and for a moment I thought I was looking at a wedge, it was a doozy."

"It was 1.20 pm approx - I saw the thing on the ground for a good 2-3 minutes continuously, although it skipped up and down for a good 5-6 minutes. It touched down as a rope, and became almost a stovepipe within seconds. The inflow winds were blowing at our backs from the north at a good 40 km an hour, and I'd say the tornado was located maybe 10 km to the west of Skipton, at Stockyard Hill?? Carranballac??"

http://backyardchaser.net/gallery/album114

I have asked Andre to display some closer shots so hopefully we'll see these tomorrow. It would appear two events had possible tornadoes.


Shauno, thanks for displaying those pics - amazing scenes of that storm and this morning's flooding !  Barely seen any weather here for the past 2 weeks and the next week looks very ordinary as well. 



Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 23 December 2007, 03:40:35 PM
Hi Michael,

Wow! We have even a stove pipe now? I fail to see any but I await the pictures - I would have thought they have been showed off already.

I cannot believe that these people are for real. But this is the same disease being spread across the board.

It is extremely important that we are able to debate observations to better our understanding and not make dubious claims as has been done in the past. Not on this forum by the way.

We may have to start another thread to discuss this component so please stick back with the topic of discussion.

Regards,

Jimmy Deguara
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Macca on 23 December 2007, 04:36:28 PM
Hi all,

I've had a bit of a read of all and sundry posted to the events which unfolded in Vic on Thursday and here is what I have been able to dicipher from this...

Andre Dalton is indicating he saw something which he believes may've been a tornado near Skipton in central western Vic at sometime around 2pm on Thursday.  He has posted photos (see earlier posts for links).  It appears to show a fairly strong storm with a thick anvil and some scud of some description under the base.  There is also a photo which shows what *could* be a funnel/tornado but without seeing motion or a closer image, it would be difficult to confirm based on this image alone.  The radar around this time indicated a strong storm with a nice "shape" on radar and movement to the left of the mean storm flow.  Harald Richter makes comment of this cell in his post which Michael kindly posted for us.  Harald says "As of 3:30z we have the northern tailend storm splitting with the leftmover
quickly dominating (nice TBSS - a sign for large hail)".
  He mentioned nothing about a meso on this storm being evidenced on radar.  I can't recall exactly but I do remember looking at that area on radar and thinking to myself at the time that there could've been a meso based on the doppler imagery at the time.  That's all I can add about that cell.

Another tornado has been reported at just before 4pm from the same area by Clyve Herbert.  The images (in this thread earlier) shown on Ch7 news are what Clyve saw.  A second-hand description of the event states "Looking towards the main inflow area Clyve was north of it at the time looking SE (it was a tail end Matilda storm). It generated a thick thumb shaped funnel then a separate rope funnel then the tornado was in between the 2 of them. The tornado appeared out of the rain area, moving northeast. Moved fairly steadily northeast while the area of convergence at the rear of the storm remained almost stationary. The tornado became rapidly rain wrapped in the later stages & pushed out a very strong cool outflow".  It is difficult to pinpoint the radar imagery which correlates directly to the report as we don't have a specific time at this stage and there are several storms/line of storms in the vicinity of Skipton at the time (ie within 10-15km E and W of Skipton).  Without knowing the exact position and time of the report, it makes it difficult to assess the radar imagery.   I think seeing more of the video and possibly more photos of the storm, as well as further details on location, time and any damage observed will help clarify what exactly happened in this case.  Oh - and the doppler imagery (and hi-res radar...lol...am I asking for too much?)  I'm sure those involved will get this information online as soon as they have time (we are only 3 days out from Christmas and I'm sure we all have plenty of other committments at this time of year). 

Conditions on the day were quite good with the sounding showing 25-30knts in the lowest 100mb from the N and this was overlayed with a 35-40knt westerly at 700mb (and continuing to strengthen up through the atmosphere).  Surface winds based on the obs at various AWSs around the area show a general NE'ly surface flow of around 15knts, gusting up to 25knts at times.  That's pretty decent shear in my book.  Obs in the *general* area indicate surface temperatures in the early afternoon being around 26-28C with DP's in the 16-18C range.  Plotting an average temp/dp combination of 27/17 from that area onto the sounding posted by Michael in this thread earlier on gives LI's of about -6 and an estimated CAPE in excess of 2000j/kg.  Given these observations, supercells would not be out of the question.  As for tornadoes, it really depends on the conditions in the direct vicinity of the storms (ie whether there was a boundary of some sort present, etc). 

I eagerly await further details on this interesting day (hopefully from the BoM who I assume will do damage assessments for these reports).  I'm also still waiting in hope for more reports to come of the two supercells over the far northern part of Vic which then turned sharply left and ventured into NSW.  (Hail up to 3 inches was reported from Deniliquin from one of these cells!).

(As was feared, yesterday clouded over rapidly over the entire state (of VIC) with the only chaseable area pushing into S NSW around Hay where there was a massive storm...and I didn't want to venture that far so stuck it out at home...good thing too...we got 15mm in 10mins last night and our kitchen flooded...hehe). 

Macca
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: David C on 23 December 2007, 04:58:52 PM
Hi Michael,


I cannot believe that these people are for real. But this is the same disease being spread across the board.


Jimmy Deguara

Let's wait and see what eventuates, since, and as Macca suggested above, supercells and possibly tornadoes are not out of the question given the kinematic wind fields and thermodynamic conditions. A storm with nice structure like that is wonderful in it's own right IMO and some of these were nice supercells. 

BTW, the pics form the other link Michael posted show a wall cloud, possibly, but no tornado.

[post edited: parts of my post were out of context and not directed at Clyve in anycase, so I have deleted them. Apologies to any Vics who thought they were being targetted ! ]
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: James on 24 December 2007, 01:50:25 AM
Just further to my rant on the Deniliquin supercell (Thursday, page 1 of thread). Macca sent me a link to some photos taken in Deniliquin itself of the hail and what looks to be some really nice cumuliform anvil structure. These images were taken by a Weatherzone Member called Dusty Plains who is based in Deniliquin. I have asked to see if he has any more photos, video or information on the storm. His comments on it so far "received 24.5 mms in 10 mins averaging golf ball sized hail with stones up to 3". man there's some damage here".

(http://i155.photobucket.com/albums/s313/cjg_012/100_8212.jpg)

(http://i155.photobucket.com/albums/s313/cjg_012/100_8213.jpg)

Cheers,

James

Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: James on 24 December 2007, 03:03:42 AM
Part 2 to my above message - some more detail on the storm hitting Deniliquin. "The structure looked like normal convection for about 45 mins then a lot of low level scud formed and the middle of the cell turned green that's when we decided to go home but only got 500 meters up the road when the gust front with golf ball sized hail hit, mixed in with it where stones 3" across. over 30 homes were de roofed in what i think was a microburst , lots of signs ripped off poles and tree damage, broken windows and cars dented ."

Also stumbled on this picture taken near Bendigo on the ABC news website. Unfortunately it doesnt have a date stamp with it so I cant confirm if its from Thursday or Friday. Im thinking more Thursday than Friday as some chasers were in the area and didnt get any structure on the Friday.

http://www.abc.net.au/reslib/200712/r213389_823116.jpg (http://www.abc.net.au/reslib/200712/r213389_823116.jpg)
Title: RE: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 24 December 2007, 04:02:35 AM
James,

Your description of the Denliquin supercell and it seems Bendigo are large fat HP supercells. Very nice indeed.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 25 December 2007, 04:51:34 AM
I just got off a call from Clyve Herbert who suggests he did see a tornado and it was the largest he has seen in this country. It achieved wedge status and he has 11 minutes of video of the event. At one stage it had a bell shape and then became rainwrapped. He suggests the Bureau confirmed a mesocyclone at the time but I asked Clyve to determine whether there was a TVS signature? I explained to Clyve that a meso is not verification of a tornado - merely that there was a rotating updraft. I assume at that distance the angle would have the beam pointing to the upper portions of the updraft. I guess we have to wait for this evidence as it would make an interesting case study.

I did ask Clyve to suggest whether he could tell if there was 'rapid rotation' even from 8 to 12 km out? It seems not. A large tornado of the size Clyve is suggesting has to have had significant rotation sufficent to be observed on zoomed in video.

We look forward to seeing this 11 minutes of footage as it will help solve the puzzle hopefully of such a significant event.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Brad Hannon on 25 December 2007, 08:06:54 AM
Thursday 20th December 2007

Hi all, certainly an interesting thread this one :) In the arvo I headed from Melb down the Princes Hwy toward Geelong to intercept some very low and intense multi-cells moving SE from Ballan/Ballarat.  I was treated to two seperate cells with wall clouds moving through the same area within 1hr of each other.

Wallcloud One
As I passed through Laverton I could cleary see directly in front of me in the vicinity of the Brisbane Ranges/Avalon a defined lowering in the cloud base.  This feature persisted for well over 20mins as I drove (excitedly) toward it and was accompanied above by what appeared to be inflow bands feeding into an updraft from the Northern side.  I have photos which show these observations and I will post these tonight.  Unfortunately the atmosphere was so dense with moisture that I never got a good view of the upper levels or overall storm structure, nor any evidence of a corkscrew updraft but from my (limited) experience (thanks to Jimmy in the US :) ) I was confident that I was observing a well organised wall cloud.  I did not observe any rapid rotation or funnel but visually the shape of the wall cloud appeared to be influenced by some rotation.  Sadly, as I got closer I could see the feature was occluding, not surprisingly in the competitive environment the cell was in.  Not long after this I spoke to a friend who advised me that chatter on the WZ forums was discussing a possible tornado up near Ballarat and possible supercells up north. 

Wallcloud Two
I pulled over near the Brisbane Ranges and watched for a while as another cell moved SE through the area.  It had a very low cloud base to begin with and a ragged scuddy area and was clearly forming a wall cloud (approx 1km away from me) with inflow from the east condensing into the updraft base.  I observed weak rotation and some isolated upward motion.  I began taking pics with my 17-40mm lens as it became a little more organised.  A small funnel began forming in the centre of the feature.  I raced to my car to get my long lens because the wide angle simply wouldnt do the job. Some 20-30secs later I snapped some pics with the long lens.  The V shape funnel was visible to the naked eye but now embedded in heavy rain and had next to no back-lighting.  There was no evidence of a tornado.  I intercepted the cell as it moved across the Princes Hwy but it had fallen apart as expected.  Meanwhile, Melbourne's East and Sth East was being belted by severe storms and torrential rain leading to floods and floating cars.  I've toyed with the question - would I prefer to have witnessed the rain and floods or the wall clouds?  I'll take the wall clouds thanks :)

Photos of these events to come tonight.





Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 25 December 2007, 09:50:13 AM
Brad,

I watched the cell approaching Ballan on radar and it had an interesting structure based on radar including a possible hook echo on one frame.

I am very interested in seeing the structure it exhibited.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Brad Hannon on 25 December 2007, 06:21:37 PM
Hi Jimmy,

Firstly, I'm pretty certain the cell you are referring to came through after the two I have described.  It was significantly larger and more intense from the description I was given over the phone at the time.  I attempted to get in position for it but it took a more E and NE track than the earlier cells.  The multicellular activity cleared to the SE and I was able to watch (as I drove thru peak hour traffic) the larger cell drift across the Northern suburbs and out to the Ranges where it had weakened as I witnessed on radar when I got home.

Anyhow, here are the pics I promised in my previous post.

1st wall cloud - looking South, Princes Hwy south of Werribee, near the Brisbane Ranges

Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Brad Hannon on 25 December 2007, 06:26:55 PM
2nd wall cloud, looking West, Princes Hwy south of Werribee, Brisbane Ranges in background.
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Brad Hannon on 25 December 2007, 06:35:35 PM
These final four pics are of the suspected funnel with a photoshop high contrast version for comparison.
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 25 December 2007, 11:56:16 PM
Brad,

The first set of photographs looks like a wall cloud and a nice one but obviously not clear and seems to break down perhaps due to competition or something like that.

The second one looks like a shelf cloud to me but then again video would confirm better.

The 'funnel' in the third set of images are hard to build a proper picture but on the picture seems to me to be fragmented scud but again video on a tripod would show more.

You obviously had a great day and lots of storms to choose from - no chance of sunburn or busts here.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 26 December 2007, 12:15:45 AM
Hi,

In fairness of a scientific debate and analysis, it is a good idea to post some other pieces of information that come to light.

Clyve sent these images via email in order to back up his claims of a 'large tornado'. I have included his times and statements with respect to the images portrayed.

------------------------------------------
Hi Jimmy as mentioned on our phone discussion I will send you stuff re the Ballarat/Skipton storms over the next few days, I don't know how to set up a video for the net but if not I will send you a DVD of the main sequence....
 
In this image taken around 1541hrsz it shows the 'tail end Charlie ( I say tail end Matilda)...This is the main inflow area and part of the left mover split. The rain behind is actually part of another storm..right moving and the northwest end can be seen. I positioned north of the storm and looking south/southwest.

(http://www.australiasevereweather.com/temp/clyve/Ballarat_flanking_line_1_1.jpg)

In this image the very end of the line (northwest end) that extended well to the east with a large RFB, again in the distance the rain is from the right splitter in a video sequence the rear lowering is rotating cyclonically and it was here I thought some action may have started however the updraft pulses were moving east along the RFB then maturing down wind of the steering mid level flow.

(http://www.australiasevereweather.com/temp/clyve/Ballarat_split_1_1.jpg)

In this image taken at 1546hrs the first funnel appeared but was short lived, I did not take still image of the rope that appeared further along the line to the east but did a video sequence of it...this funnel lasted about 2 minutes before rapid dissipation...C

(http://www.australiasevereweather.com/temp/clyve/first_funnel_Skipton_1.jpg)

This is one of the still images taken at 1550 hrs and shows the Tornado in full swing the tornado was rotating cyclonically and the wrap around banding can be seen on both sides of the tornado, I would estimate the motion towards the east/northeast around 40 or 50 kilometres per hour...

(http://www.australiasevereweather.com/temp/clyve/Skipton_tornado_2_1.jpg)

This a closer look at the tornado with associated accessary cloud elements, at this point about 1552 a skirt appeared  lower down and the central rather broad funnel it was between 8 and 10 kilometres distant...

(http://www.australiasevereweather.com/temp/clyve/zoomed_image_2_1.jpg)

In this image the tornado is just about to dissipate there is still a connection to the ground but the overall size of the rotating area is large, note the collar along the top under the main RFB, the remains after this image became rain affected very quickly as the cell collapsed..

(http://www.australiasevereweather.com/temp/clyve/Canon400D_184_1.jpg)

After the collapse of the tornadic storm a strong outflow followed and came around the rear of the main precip area to produce this veil that moved first north then northeast and finally headed east and later kicked off a strong storm east of Ballarat, I followed the outflow band from the Ballarat storm complex...

(http://www.australiasevereweather.com/temp/clyve/Ballarat_flanking_line_4_1.jpg)

After following the Ballarat outflow this storm developed time 1846hrs (Among others) but by far was the strongest however I regard this storm as outflow dominated with a constant rear downburst pulse as each updraft matured then kicked back along the flanking line....best regards Clyve Herbert

(http://www.australiasevereweather.com/temp/clyve/Guildford_Castlemaine_SC_2_1.jpg)

You have my permission to put these images on your site if you want and use my comments if you wish...Images taken with a Canon 400D 18 to 55 lens set to auto....I will also retrieve captures from my Panasonic GS 300 with a capacity of 3.2 mg stills of the entire event...Clyve  H

--------------------------------------

I will allow others to comment.

What I would like to know is how long was this 'large tornado' on the ground? When diid this 'large tornado' become 'bell shaped' and almost a wedge status? These were claims made on the phone conversation. What comments did the Bureau have of this 

Feel free to send the video and place online all unedited 11 minutes of it - we can certainly spare the bandwidth.

My point of view still stands that this feature occurs along as a result of what appears to be developing outflow. This is shelf cloud central and a nice shelf cloud in that.

I would still like to see the video before developing a proper picture.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: nmoir on 27 December 2007, 03:29:34 AM
I would like to see a damage survey on the area , surely a large or even small tornado would leave some significant signs even in a wheat field , any questions on the existance of the tornado would be answered by this easy task. To me , having never seen a decent tornado , the feature appears messy and the lack of any raised dust swirl at the base of the feature makes me suspicious , also i want to see video and rotation!

Nick
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Brad Hannon on 27 December 2007, 02:30:24 PM
Hi Nick, I agree re a damage survey for this tornado event.  Seems a lot of talk on WZ about a tornado and no-one talking about any damage path or evidence of rotating wind damage.  Hopefully some emerges, along with some video :)

By the way, that's a strapping young lad in the bottom left of your avatar!

Brad.
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Brad Hannon on 27 December 2007, 03:23:22 PM
Melbourne storms - Wed 19 December

A local chase (5mins!) took me to the highest point in metro Melbourne where I caught these images at dusk.  I returned to this spot after 9pm to watch a short lightning display over the city.
Brad.

Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Richary on 29 December 2007, 01:11:36 PM
Hello, now it appears that NSW got a tornado out of that as well...

"A mini-tornado that last week damaged Lake Cargelligo's main water pump is being blamed for the deaths of 200 tonnes of fish that washed up on its shores."

http://news.smh.com.au/riverina-tornado-caused-dead-carp/20071228-1jc7.html

Whether anybody saw it, or it was just a downpour and high wind who knows?
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 30 December 2007, 04:24:11 AM
Hi,

Here are some other items from Clyve's conversation with Harald Richter (with permission from Clyve):

initial email:

hi Harald...still shaking in my sandals after bagging this tornado between Ballarat and Skipton, will send details taken at 1551Z on wide angle lens...It was a big tornado and developed very rapidly, there were two funnels at different locations prior to this setting down....The tornado became rain wrapped rapidly and dissipated after about 5 to 6 minutes, however the area of vorticity remained after dissipation with a lot of scud rotating over a wide area..very weird stuff...regards Clyve H

Harald's response:

Congratulations Clyve,

I have been training in QLD for the past 6 weeks, hence my slow response.

It seems to me that you have bagged a QLCS tornado that spun up
on the leading base of a NNE propagating line.  In the wake of
this line Ballarat cooled to a chilly 18.4 C (after 5z) with SSW winds.
Initially I thought you got onto the earlier (3:30z) supercellular activity
between Ballarat and Skipton, but eventually decided that you probably
worked the 4:50z linear segement.

The Melbourne Doppler shows that the dominating cell within the line was
located about 8 km WSW of BLT at 4:40z, the time of your observation.
I can see a number of cyclonic couplets at low levels on the 4:48z
scan, but no decent midlevel rotation.  Maybe we should sit down and
look at the data one day.

Have a stormy start to 2008,
Harald

Clyve once again to me:

Hi Jimmy...reply from Harald...Suspects a QLCS (Quasi Linear Convective system) generated Vorticity max west of Ballarat. Although will have to do a deep study on the occurrence. Strong convection may have taken advantage of the cyclonic couplets operating along the QLCS which may explain the two short lived funnels appearing before the main event...Appears tornadic developments can occur under a number of set-ups, seems if the dynamics are good a number of initiating triggers can go down the tornado generating process...regards Clyve Herbert.

-----------
Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 30 December 2007, 04:26:27 AM
Further conversation regarding another cell:
------------

Hi Harald..Later in the evening followed this big storm from Creswick to Castlemaine (formed on outflow of Ballarat complex)...Note the rear outflow along the ground and under the flanking line....I suspect this storm may have achieved supercell status...regards Clyve H


Harald's response:

Hi Clyve,

I agree with your supercell suspicions - the storm had
a deep and persistent mesocyclone on radar, moved left of
steering and showed a persistent TBSS (hail spike).
Nice catch, and this one has some impressive radar data
to go with the impressive visual you took.

Harald

Hi Jimmy also appears that the storm south of Castlemaine later that day may have been significant although I did not see any rotation of significance near the inflow outflow interacting interface..regards Clyve H....PS If you want you can put Haralds comments up on the images applicable...

-----------
Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 30 December 2007, 04:59:31 AM
In relation to the comparisons of TVS strength signaures relating to tornadoes generated by supercells and those occurring along Quasi-Linear Convective Systems (QLCS)

(http://www.cimms.ou.edu/%7Ekmanross/QLCS/Img/Avg/tTSI.gif)

Taken from an extract of the article:

http://www.cimms.ou.edu/~kmanross/QLCS/QLCS_-_TWG_Comparison.html

In my opinion, if this was indeed a tornado Clyve has captured, there is a high likelihood it was not a large tornado based on this data set and also visually. I fail to see a significant and consistent debri cloud associated typically with large tornadoes. I do see outflow in one of the earlier shots.

We still would like to see the 11 minutes of video associated with this ' large tornado'. This would clarify so much in the behaviour of the storm as a whole. I will post it immediately once supplied as well as results from a damage survey.

We can conclusively suggest that this is a 'possible' tornado.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: flipwx on 30 December 2007, 05:03:50 PM
Clyve has put up a load of new photos here: http://www.stormchasers.au.com/20_12_07.htm

However, I'm still not sure why it is so difficult to put the video online instead of just captures!
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Richary on 30 December 2007, 05:19:18 PM
I am certainly no guru on this but while there was a funnel shaped thing coming down from the cloud base, I see no evidence of a tornadio. Given my very limited experience in this I would just say it was cloud. Having seen those photos unless there was a damage trail on the ground I just don't think it happened. The funnel as such was not well defined, no debris and no clear evidence of rotation.
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Mike on 30 December 2007, 07:17:46 PM
Mmm yes I'd have to take an educated stab and also say it's a tornado.  It's attached to the cloud base, there was visible rotation mentioned and there is a condensation skirt around it - like Jimmy eluded to, without the video it's really hard to pinpoint every detail, the video would definitely confirm it.  Perhaps some more pursuation may get it on the forum?

With my limited knowledge of such things also but I'm confident of it being just what most have said - a visible grounded funnel.

Mike
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 31 December 2007, 04:07:46 AM
Hi Mike,

I am just curious as I may have misinterpretted it - do you think it is a tornado or not a tornado? Yes said it is a ground funnel? Just a little confusing to clarify. Perhaps get Reed Timmer into this discussion during their quiet time Mike.

My point again - rotation is difficult to assess and the claims for the whole time of conversation is that this was a 'large tornado' to 'wedge tornado' - that it is not. Rotation is difficult to determine from the quality and brief duration of video provided on media.

Video stills without sufficient information is pointless. You take it - Clyve suggests the tornado was on the ground for 5 to 6 minutes. Even taking 5 minutes into consideration - at 25 frames per second even, you have

5 x 25 x 60 = 7500 possible frames

Unless we know the times of these specific stills, it is a useless exercise in verifying ground contact for the full duration of 5 to 6 minutes. This is why he raw video is important.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 31 December 2007, 05:28:31 AM
To add to the link Phil suggested above, here is a excerpt with the link:

------------------
Hi Harald,
 
These are captures from the video sequence with some basic descriptions. 
http://www.stormchasers.au.com/20_12_07.htm
 
I had a look at the public available radar and noticed the significant storm appearing north of Cressy which appears to show a large hook echo of sorts, and then I suspect a propagating boundary moved northeast to generate the QLCS as suggested by you.  It was interesting your mention of decoupled vorticity - could this explain the 2 funnels along the line prior to the 'main event'?
 
The sequence shows what I initially missed at the start - behind the lowering which I dismissed as scud, closer examination shows what appears to be a ground connection of vorticity.  The tornado developed very rapidly to the point where I was overwhelmed by how quickly things went from that point.  Interestingly the 2 funnels didn't appear to move very much, but the tornado, after developing, moved to the ENE quite rapidly.  In the final sequences, rain appears to wrap around the vorticity centre which now develops into a large bell shape with a collar.
 
I hope these images will be of use in your research in atmospheric oddities, and I would be very happy at some stage to go over the video and get a deeper understanding of the processes particularly with your radar analysis and experience in severe weather.
 
best regards.....Clyve Herbert

---------------------

Phil, given you saw these video stills, what are your thoughts from what you see?

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Mike on 31 December 2007, 07:48:33 AM
Yes, thought it looked like a tornado given its structure and going on what i've read, seen etc on a limited basis.  I would also like to see if there was any damage path whilst it was grounded.  I shall ask Reed to jump on and have a look at this thread for his input.

Mike
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 01 January 2008, 02:07:06 AM
I have received feedback from Gene Moore, who has seen more tornadoes than most chasers, suggests unless the video is void of motion, then there is no doubt it is a tornado. The video supplied is fairly poor quality in determining the existence of motion.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Mike on 01 January 2008, 11:21:24 AM
Hi Jimmy, Reed is looking at the photos as you asked and will get back to me asap on this topic.  He'll either post a comment or relay the info via email for me to paste.  Gene's expertise in this area is infamous and this thread has received some excellent comments from all regarding the event.

Mike
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 01 January 2008, 02:28:55 PM
Chuck Doswell has also commented suggesting that he tink the latest stills show a tornado. Again he awaits to see if there is motion visible.

Regards,

Jimmy Deguara
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Gambit on 02 January 2008, 01:03:30 PM
Hi all,

Jimmy has the video been posted anywhere i.e. youtube or anywhere else in the public domain? Or is that what everone is waiting for???

Cheers

Mathew
Title: Re: SE Aust Severe Storms (incl possible VIC tornadoes) 19 - 22 December 2007
Post by: Jimmy Deguara on 02 January 2008, 01:39:16 PM
We can almost confidently say now with the most recent video stills that the feature is in the form of a funnel. The video would just confirm more in terms of motion.

Clyve is rather busy at the moment but is making every effort to ensure some possibility of getting it online.

Regards,

Jimmy Deguara