Storm Australian Severe Weather Forum
Severe Weather Discussion => Australian Severe Storms, Weather Events and Storm Chasing => Topic started by: David C on 06 February 2007, 12:43:42 PM
-
Central West Slopes & plains, Northwest Slopes & Plains, possibly adjacent tablelands:
Paul gave me a heads up that the week ahead is looking good.....but I must say I was not expecting -8 Li when I checked GFS just now!!! If that eventuates, it looks as though there will be sufficient shear for some intense storms.
At this stage Tues looks ok while Wednesday and Thursday look very good. Things change and will look in greater detail tomorrow, but keep an eye out. Of course, it would be a week day ::)
-
You beat me to the topic...!
Wednesday certainly looks fairly good on paper. Shear in the first 300-400mb if the surface winds stay NE and get over 15-20knots will be quite healthy, perhaps being strong enough for the S word. Upper level shear is ordinary.
Whilst at this stage the Central tablelands and slopes look the goods I would gamble for the extreme upper Hunter around Mudgee / Gulgong - my reason is that the model runs so far indicate little CAP so the mountains may explode off far too early and the lot become a thundery complex.
Another favourable aspect is the the upper shear is still west, if it was SW as often is the case it would spread anvils towards the inflow.
-
The latest run for tomorrow the 7th is looking very very good for the Central Ranges. It is now showing moderate CAPE and LI now as well as very high lapse rates. The development tomorrow should be explosive, even atomic bomb type explosive. The only dilema I can see will be the steering winds. Storms will develop and go straight into no mans land so I can only hope that western Sydney is affected by this.
-
Quite a marked dryline in NSW today (6th ) - current dewpoint in Dubbo is -3C, yet at Mudgee 14C.
Gunnedah 3C, Tamworth 12C
Similar pattern all up the slopes.
GFS has now moved activity for the 7th well and truly to the tablelands, although I still think any 'S' chance will be in the extreme upper Hunter after 3pm.
May now start my day from Goulburn and head nothwards towards Oberon, before a late afternoon in Mudgee.
Tomorrow mornings satellite and DP's will decide that fate.
-
Quite a few severe storms underway though split in 3 distinct areas along the tablelands for now: near Cooma, between Bathurst and Taralga, and east of Guyra. STW is for large hail in all three areas.
Issued at 2:51 PM Wednesday, 7 February 2007.
Severe thunderstorms are likely to produce large hailstones in the warning area over the next several hours.
Major locations within the warning area include Cooma, Wollongong, Nowra, Bowral, Bathurst and Katoomba.
-
Holy cow! Quite a few cells moving through there on the radar!
Is there some particular feature of that part of NSW that sees these severe storms on a regular basis? Perhaps someone could advise as to the weather patterns through this large area when this happens. I'd like to know.
Mike
Hope your'e all out chasing and be safe!
-
I've just got off the plane from Sydney to Narrabri - next time I think I'll walk!
We were held at Sydney Airport for 1.5 hours as the tarmac was closed for a 'lightning alert'. Once we made it into the air things were very choppy until we got over the mountains and up to cruising altitude. We had to fly out past Dubbo and zig zag the whole way north to avoid the worst of the weather (credit to the QANTAS pilot who did very well).
There was once little patch of forest, probably between Gunnedah and Boggabri, only a few km from our flight path, that I counted 30+ ground strikes on in just a few minutes, I could see a small fire burning there, but fortunately the rain expanded shortly afterwards and hopefully extinguished the fire.
As we came in to land - choppy again - I was busy trying not to think about microbursts. Fortunately the winds were fairly calm at ground level and we got all wheels on to the tarmac no worries.
I tried to get some photos but I don't think they'll turn out very well. The worst thing was, it was so choppy that the steward refused to serve the complimentary beer!
Regards,
Dave
-
Have you seen "Blizz's" photo of a possible tornado extending from this wall cloud?
Tornado, or pressure lowering where the inflow is getting excited?
Would you more often expect tornados to be towards the rear of the rain-free base?
Blizz's Photo:
http://www.blackheathweather.com/generalphotos/severestorm7-2-07-03a.jpg (http://www.blackheathweather.com/generalphotos/severestorm7-2-07-03a.jpg)
Please do not post links to WZ forums. You may mention them but no linking.
-
I just got back from a superb chase today. I didn't get to Lithgow in time to see the classic supercell but Jimmy, Dave and Paul did. I saw the footage tonight and it is awesome to say the least! Anyway I got to Mt Victoria just after the 6cm hail was reported near lithgow by Jimmy.
I caught the tail end of the supercell at Hartley Vale and witnessed lots of hail on the ground, an awesome hail fog and some awesome flash flooding as well as ash and mud La'hares from the deforrested moutains! I tried to drive from Hartley Vale up to the Darling Causeway but the road was blocked by larges rocks, mud and other debri from the torrential rain they recieved.
As for the question of the wall cloud feature, Jimmy and the others witnessed most of it's life and they didn't mention seeing a tornado. There were quite a few tail cloud formations as well as general scud around the wall cloud. It has definate rotation but I don't believe there were any tornadoes.
Of interest as well would be possibly the longest Beaver Tail I have ever seen which stretched for at least 10km's into the front of this cell. I saw it form as i drove up the mountains and photographed it at Hazlebrook.
Jeff.
-
What an awesome storm -
Chased with Jimmy and Paul and later met up with Jeff and Matt.
Highlights:
- slow moving classic supercell that initiated west of Lightgow (south of Bathurst).
- observed violent (dont use the term lightly either and compare this with tornadic storms I have seen in the US) storm scale rotation at lithgow. [gate to gate shear would have been impressive no doubt]
- numerous wall clouds (and IMPRESSIVE tornado wannabes)
- measured 6 cm hail that fell on us as we were under the vault just south of Lithgow.
- observed another impressive, HP storm that eventually merged with the classic storm. Trees limited the view of this one although the structure was absolutely green and VERY interesting (see last pic below).
- impressive lightning
- Video stills below.
cell early on
(http://www.thunderbolttours.com/stills_au_07/0702200701.jpg)
more impressive
(http://www.thunderbolttours.com/stills_au_07/0702200702.jpg)
better still
(http://www.thunderbolttours.com/stills_au_07/0702200703.jpg)
(http://www.thunderbolttours.com/stills_au_07/0702200705.jpg)
what the....
(http://www.thunderbolttours.com/stills_au_07/0702200708.jpg)
weakened a little and reorganised and base lowered
(http://www.thunderbolttours.com/stills_au_07/0702200710.jpg)
Heading east towards Lithgow...beaver tail ahead
(http://www.thunderbolttours.com/stills_au_07/0702200712.jpg)
multiple inflow bands and beaver tail meet the supercell base
(http://www.thunderbolttours.com/stills_au_07/0702200713.jpg)
At Lithgow, storm above was VERY impressive now (needed fish eye lens but video will be amazing
(http://www.thunderbolttours.com/stills_au_07/0702200714.jpg)
(http://www.thunderbolttours.com/stills_au_07/0702200715.jpg)
(http://www.thunderbolttours.com/stills_au_07/0702200716.jpg)
beaver tail / updraft base interface
(http://www.thunderbolttours.com/stills_au_07/0702200717.jpg)
rotation was even more incredible here. Jeff has a shot looking north at what was above us
(http://www.thunderbolttours.com/stills_au_07/0702200718.jpg)
hail begins falling from the vault above us
(http://www.thunderbolttours.com/stills_au_07/0702200719.jpg)
we copped a hiding from this giant hail - 6cm measured and which Jimmy reported to the BoM
(http://www.thunderbolttours.com/stills_au_07/0702200720.jpg)
green hp (suspect) through the trees - you be the judge of the 'funnel'. This storm was also amazing but we could not get a clear view before it rolled over us.
(http://www.thunderbolttours.com/stills_au_07/0702200721.jpg)
Enough from me. I'll let Jimmy and Paul posts some pics and their impressions of this memorable chase. Will throw some flash video up soon.
-
Hi Jeff and John,
Perhaps they should have issued a tornado warning - at least this time the warning would have been warranted. I even called in the 6cm hail report and added classic supercell to my report with my name:) I hope that I would have been classed reliable enough haha.
(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd07.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd07.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd08.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd08.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd14.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd14.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd19.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd19.jpg)
(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd24.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd24.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd26.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd26.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd27.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd27.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd29.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd29.jpg)
(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd40.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd40.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd42.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd42.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd49.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd49.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd53.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd53.jpg)
(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd56.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd56.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd57.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd57.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd62.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd62.jpg)(http://www.australiasevereweather.com/photography/thumbs/2007/0207jd64.jpg) (http://www.australiasevereweather.com/photography/photos/2007/0207jd64.jpg)
All pictures from the day here:
http://www.australiasevereweather.com/photography/photos/2007/jd20070207.html
I would like to add here a thanks to Ray, Michael and Nick for their phone calls and/or messages. I normally forget to mention because I hardly use back up. But when things are not working according to plan, the mind ponders I guess. Strangely enough though, the supercell both David and I almost spoke on top of one another when we noticed it had inflow and then decided to move towards it.
Regards,
Jimmy Deguara
-
Dave, your images turned out really well - they were from the video capture I presume?
Here is my report of the day: http://stormchase07022007.blogspot.com
Please note that you have to click on "older posts" at the bottom of the page in order to see page 2. I'm trying to find out a way of showing it all on one page but haven't been able to yet :(
Cheers,
Paul
-
Hi all - some photos of the storms during yesterday's chase from Mudgee to Scone.
(http://www.australiasevereweather.com/rodney/20070207rjwa.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwb.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwc.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwd.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwe.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwf.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwg.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwh.jpg)
-
A gustnado sequence near Merriwa looking generally westward. Hopefully some of the other guys (their headlights can be seen in the bottom left on some of these images) who were looking at it from the other side and may have video.
(http://www.australiasevereweather.com/rodney/20070207rjwi.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwj.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwk.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwl.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwm.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwn.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwo.jpg)
(http://www.australiasevereweather.com/rodney/20070207rjwp.jpg)
-
Terrific photos of the very significant storms yesterday by everyone !! Wish I had been able to chase but too far mid week for me.
Would anyone like to explain why the Lithgow cell rotated so rapidly ? The shear does not appear to be that strong on the GFS analysis, or on any of the soundings I've seen.
Links to GFS Analysis: Wednesday 07/02/2007 06z
Instability: CAPE (http://australiasevereweather.com/storm_news/2007/maps/2007020706cape.png) / Lifted Index (http://australiasevereweather.com/storm_news/2007/maps/2007020706li.png)
Relative Humidity: 0300 (http://australiasevereweather.com/storm_news/2007/maps/2007020706rh0300.png) / 0500 (http://australiasevereweather.com/storm_news/2007/maps/2007020706rh0500.png) / 0600 (http://australiasevereweather.com/storm_news/2007/maps/2007020706rh0600.png) / 0700 (http://australiasevereweather.com/storm_news/2007/maps/2007020706rh0700.png) / 0850 (http://australiasevereweather.com/storm_news/2007/maps/2007020706rh0850.png) / 1000 (http://australiasevereweather.com/storm_news/2007/maps/2007020706rh1000.png)
Temperature: 0300 (http://australiasevereweather.com/storm_news/2007/maps/2007020706tmp0300.png) / 0500 (http://australiasevereweather.com/storm_news/2007/maps/2007020706tmp0500.png) / 0700 (http://australiasevereweather.com/storm_news/2007/maps/2007020706tmp0700.png) / 0850 (http://australiasevereweather.com/storm_news/2007/maps/2007020706tmp0850.png) / 1000 (http://australiasevereweather.com/storm_news/2007/maps/2007020706tmp1000.png)
Winds (knots): 0200 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0200.png) / 0300 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0300.png) / 0500 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0500.png) / 0600 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0600.png) / 0700 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0700.png) / 0850 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0850.png) / 0925 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind0925.png) / 1000 (http://australiasevereweather.com/storm_news/2007/maps/2007020706wind1000.png)
Interactive radar loops for 7th February
Kurnell 128 (http://australiasevereweather.com/storm_news/2007/radar/20070207/sydney(kurnell)128.htm)
Sydney 128 (http://australiasevereweather.com/storm_news/2007/radar/20070207/sydney128.htm)
Sydney 256 (http://australiasevereweather.com/storm_news/2007/radar/20070207/sydney256.htm)
Newcastle 128 (http://australiasevereweather.com/storm_news/2007/radar/20070207/newcastle128.htm)
Newcastle 256 (http://australiasevereweather.com/storm_news/2007/radar/20070207/newcastle256.htm)
Newcastle 512 (http://australiasevereweather.com/storm_news/2007/radar/20070207/newcastle512.htm)
Regards, Michael
-
Hi Michael,
Yes the shear on the day may not have been what one believes incredible but it was definitely sufficient and remember we were at near 1000 metres above sea level - so bases were not high. Second, the storm became anchored - I can only assume this given the storm was not moving at the same pace as others on the day in some cases with less shear. It was I believe on a triple point - something that will not generally show on our GFS resolution models (lack of data).
Also be careful when considering simply shear alone. There was meant to be high instability - you require less shear with higher instability. However, if a storm develops and anchors on a triple point - ie its existence and behaviour is dictated by the conditions near the triple point, then it has an advantage as winds from various directions can aid low level vorticity. COnsider 5th June 2005 in the US ok 6000CAPE but less wind shear than this. However, despite the HP supercell nature of this storm it moved sharply right and also developed near the intersection of a retreating warm front, dryline creating a triple point. This storm produced a decent tornado! The rotation was significant!
I hope that helps. This is what I mean about people acquirign ample knowledge simply by going on even one US trip!
I am still on a high with this!
Regards,
Jimmy Deguara
-
Don't worry - I am not going by shear alone :) It helps to have things explained as we use exactly the same data (low res GFS, sparse sounding network, AWS Obs, radar) to analyse other events around the country (to help determine supercells or not), so it's important to know why this stands out. Obviously photographs and video of structure and rotation are the key.
MB
-
Hi Michael,
I've estimated the mean surface to 6km shear vector to have a magnitude of around 35 kts (based on yesterday afternoon's Sydney sounding - the situation in the storm zone wind-wise probably was not too much different). From what I understand, supercells require a value of greater than 30 kts. So that puts yesterday's conditions within the threshold.
Cheers,
Paul
-
Hi Michael,
Sometimes, storms become extradordinarily severe even beyond what the conditions were suggesting so that cannot be ruled out. I guess this is not about whether this storm was the most significant ever recorded or better than others in this season or other seasons, it was significant in its own right. Classic supercells are the most efficient tornado producers so naturally the rotation would be more visible. But in this case, from the updraft to the inflow and beaver tail, rotation was clearly evident in real time. But over Lithgow, the rotation over headed was as David suggested comparable to some supercells we had observed in the US.
Outflow at no point whilst we were observing cut through which was amazing in my opinion. Usually that is what I look for - what will spoil the party this time around. Take for instance the 7th December 2004 event. Rain descended from behind and the storm became HP not long after. There was no problem like this yesterday.
Regards,
Jimmy Deguara
-
Paul - I'm not saying the shear plotted on GFS or the soundings did not support supercells - it certainly did support them. I was just questioning why this one became so intense with the strong rotation described by you guys who were there. Jimmy has provided some answers to that.
Regards, Michael
-
Scone sure experienced a prolonged period of severe winds as that storm passed by (from 6.18 to 6.49 severe gusts) :
07/07:59pm 23.2 21.3 16.8 67 4.2 S 22 28 12 15 1004.7 1.0
07/07:03pm 24.0 23.2 16.1 61 5.2 NNE 15 57 8 31 1002.7 1.0
07/06:55pm 22.0 15.7 16.1 69 3.9 SSW 44 67 24 36 1001.7 1.0
07/06:53pm 22.3 15.6 16.1 68 4.1 SSE 46 76 25 41 1001.8 1.0
07/06:49pm 21.3 13.4 16.9 76 2.9 S 54 95 29 51 1002.0 1.0
07/06:45pm 26.5 16.1 12.6 42 8.8 S 59 95 32 51 1001.5 1.0
07/06:39pm 19.8 10.6 17.0 84 1.8 S 61 80 33 43 1002.3 0.8
07/06:34pm 20.5 11.4 16.2 76 2.8 SSW 59 113 32 61 1003.0 0.0
07/06:27pm 22.5 9.0 14.1 59 5.3 SW 78 113 42 61 1003.3 0.0
07/06:20pm 28.6 16.2 14.1 41 9.4 WSW 72 109 39 59 1001.9 0.0
07/06:18pm 30.4 22.3 14.5 38 10.4 WSW 50 100 27 54 1002.0 0.0
07/06:17pm 32.7 25.9 14.4 33 12.1 WSW 43 70 23 38 1002.2 0.0
07/06:00pm 35.4 36.0 11.8 24 15.2 CALM 0 0 0 0 999.3 0.0
07/05:00pm 36.4 34.6 12.0 23 15.8 NNW 13 20 7 11 1000.9 0.0
Check the Newcastle loop for matching radar:
http://australiasevereweather.com/storm_news/2007/radar/20070207/newcastle128.htm
Also a couple of soundings for reference:
http://australiasevereweather.com/storm_news/2007/soundings/2007020704sydney.png
http://australiasevereweather.com/storm_news/2007/soundings/2007020700williamtown.png
-
Hi Michael - Sorry for the confusion. Yes, it was an awesome sight to witness and reminded me of the video clips I've seen of storms in the US. I wonder if in addition to instability, topography may have also had an enhancing effect, at least to the lower levels of the storm?
Cheers,
Paul
-
Nice photos everyone.
Hi Paul, yes they are video frames. Your report at blogspot is excellent too, hope everyone takes a read of it!
Not surprised at the winds from the storms further north based on photos and radar -- high-based with lots of dusty outflow evident.
-
Hi Rodney,
Those gustnadoes were awesome - very tight circulations! And so was the storm structure. I recognise the locality of those undulating hills.
Rodney, does anyone have some pictures of the storm when it was in its classic stage? Ben suggested classic supercell tending to HP supercell? I can only see HP structure from the pictures.
Regards,
Jimmy Deguara
-
Good afternoon.
I dont think anybody was chasing the South Coast and ajacent ranges. Some intense echoes were picked up on the ranges west of Moruya yesterday afternoon. It might be worth posting the Canberra radar loop as well. It was very interesting down that way!
We chased the Goulburn/Taralga area yesterday.Some high based scraps brought some suprise close CGs quite early in the day.These cleared off towards the coast leaving us with clear blue skies. Strong development could be seen to the far south but this was 3 hours away. More activity could be seen to the north towards Lithgow. At about 3PM we met up with Michael Thomas at a servo in Goulburn. By now a very solid anvil could be seen to the distant north spreading to the NE probrably over Sydney. 5PM,and we finially saw updrafts to the northwest of town.These built very quickly and before we knew it we had a storm. This storm pumped out some nice CGs before moving away to the southeast,this was when Michael Thomas left us.Soon afterwards another dark base developed rapidly overhead letting out a few flangs. This was the start of the storm which moved through Bungonia and Nerriga maintaining black echoes for a good hour.
(http://img.photobucket.com/albums/v168/pingtang100/P1010715edit.jpg)
Some of the updrafts at the back of the storm were quite explosive. I have some footage of this storm and the powerful updrafts but unfortunatly no timelapse. The storm moved towards the southeast quite quickly moving into unaccessable bushland. Heres a few more pics of the storm.
(http://img.photobucket.com/albums/v168/pingtang100/P1010725editt-1.jpg)
(http://img.photobucket.com/albums/v168/pingtang100/P1010713edit.jpg)
The Bungonia storm was definatly the highlight of my day. Its just unfortunate the action was so shortlived.
-
Have added the Canberra radar loops as requested. Should have put them up earlier with the other lot !
http://australiasevereweather.com/storm_news/2007/radar/20070207/canberra128.htm
http://australiasevereweather.com/storm_news/2007/radar/20070207/canberra256.htm
-
Pintang,
I actually quite like the storms you have chased here. The region you were in was in a slightly better environment for upper level cooling thence the explosive development. I could see some of those storms further south. For me it was game over to get to them from Lithgow. Some powerful updrafts as you suggest and you can see a distinct lowering in the second photograph.
I found it interesting how there were weaker storms in a line and then suddenly they decided to venture another level into the atmosphere. This on the sounding was the most unstable component of the trace and it is great to see things in action.
Regards,
Jimmy Deguara
-
I did a rough edit video timelapse of this supercell linked here:
http://www.australiasevereweather.com/video/movies/2007/classic_supercell_rotation_february_7_2007.wmv
Regards,
Jimmy Deguara
-
Hi Jimmy re other pictures of the Storm in its more classic form... I have lots of pictures but at some stage we may have missed the inflow dominate stage.I'm yet to look at all of my pictures to see if I could produce anything close to those requirements as it was inside my comfort zone a lot of the time .....Clearly a few of us were all taking pictures so may be able to complete a well documented angle as the next few days pass.
-
loved the timelapse jimmy. and well done to all chasers on the lithgow and mudgee storms
-
We went for a drive Narrabri/Boggabri/Mullalley/Coonabarabran/Narrabri yesterday afternoon. Before dark a few nice cells had formed in the area, such as this fella over the pilliga forest:
(http://narrabriweather.net/events/DSC07338-thumb.jpg)
The LI was pushing -5 but there was very low shear so I doubt there was any rotation in the cells, but I'll offload the timelapse and have a good look tonight.
One other thing that really stood out - between Mullalley and Coona we noticed where the tornado crossed the highway two years ago. The tree damage was astonishing but there is a fair amount of regrowth now.
Regards,
Dave
-
Hi all,
I'd just like to say that the timelapse footage is superb. It really illustrates the intense inflow and rotation well.
-
Jeepers. Totally insane and textbook stuff! Great photos and reports. The place was going off its head by the sounds of it. even my mate in Oklahoma viewed the soundings and LI/CAPE graphs and wanted to know if I was going to chase with you guys - well sort of if i want to drive 1800km SE to beat the cells!!!!!
Fantastic viewing guys! I'm envious as hades.
Mike
-
Hello
The photographs are awesome. Fantastic pictures.
I was aware of these storms but was at work.
However, before I left work Wednesday, I was watching on the Canberra radar with Merryn a significant Supercell storm SSW of Braidwork and south of Canberra. Are there any reports on this and what it was doing? It was sustaining rainfall at the top end of the rain scale for quite some time and clearly had rotation.
It was curving NE but sustained a very large core.
Even Merryn who knows little about storms could make out rotation. There was even a smaller storm behind it that also rotated but tracked SE.
It was part of a cluster but the big supercell referred to was at the northern edge of this cluster. Any reports on this storm would be worthwhile especially given its size.
I was watching the Blue Mountains storms as well. While I could not get out to chase them I was rewarded with a beautiful sunset and mammatus formations at sunset which I photographed. Normally I do not photograph these but in this instance, the light, sun angle and the brilliance of colours and reds made it worthwhile.
Harley Pearman
-
Hi Harley,
First, conventional radar do not exhibit rotation although they exhibit features that may be linked to rotation. I am not suggesting it was not a supercell, but we must be careful about labelling storms as such without evidence of perhaps deviant motion or features such as a hook echo.
The other important point is that I believe the Canberra radar over estimates it's echos making the storms look far more impressive than they really are. I made this comment on the thread on last Saturday's 3rd February storms - comparing one storm with two radars getting two different intensities.
Regards,
Jimmy Deguara
-
Jimmy,
Is it a case of over estimation or could it be simply that it's a new radar with better resolution than the old Sydney Radar.
Jeff.
-
Hi Jeff,
You possibly could be correct but that would be embarassing if Sydney (population 4 million) is using an old style radar. I am open to any other suggestions but I know that both radars are not reading the same into the same storms.
I wanted to also suggest that since then I saw radar of the cell Harley refers to. It is very linear and does not seem to indicate supercellular behaviour. Certainly the claims of observing rotation on radar is certainly unfounded.
I have spoken to Harald Richter to get some higher resolution scans of the supercell. He suggests that he can pick out 2 supercells on the day so it will be interesting which ones they were.
Regards,
Jimmy Deguara
-
Jimmy,David and Paul,
Very impressive timelapse and stills of the Lithgow supercell. On a day where the atmosphere is exhibiting such a dynamic setup, how do you decide which location will give you the opportunity that combines all the ingredients so brilliantly as Lithgow?.
The rotation in that storm is so fluid and organised, it is a joy to watch. Rotation in nature whether it be floodwater whirlpools or classic supercells is a discovery process for us all to enjoy.
Cheers to you all, Con.
-
If you take a look at the Sydney radar loop I think you might be right Jeff. The supercell that we chased was producing 6 cm hail although radar reflectivities were not really indicative of the storm's intensity for the most part. I don't think attentuation, due to other storms being in the path of the beam, should have been a problem.....at least until near it's demise when the southern storm merged with it and disrupted it.
I think conditions last Wednesday favoured large hail and Canberra radar reflected that.
Regarding Haralds ID of two supercells: There was an interesting storm that tracked southeast in the Mudgee area and a few on the southern tablelands that looked interesting. I'm not convinced that the Merriwa stuff was supercellular, although was intense. Clearly multi-cellular behaviour until east of town -- cell merger there and larger updraft develops.....possible HP which tracked just to the south of Scone. These are my impressions based on the radar.
-
Jimmy
Thank you for your answer. It was certainly an interesting storm cell that I was watching on the Canberra Radar.
If you do get further advice, I was watching it between 4.45 pm to 5.15 pm Wednesday night and it was showing an intense storm south of Canberra during that time (Then again, I hope the radars are actually picking up what is really going on).
I am aware that two different radar observations can give two different views of storms and rain cells and I see that when looking at the Sydney and Newcastle radar.
Harley Pearman
-
Two other possible factors that came to my mind were the elevation of the Canberra Radar and the fact that it often has a clearer veiw of the back of storms to it's north than the Sydney raday would by looking more westerly.
Some pics from the 7th
Beaver Tail
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_016.jpg)
Supercell Updraft post Hail
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_050.jpg)
Mud, debri and flooding over road plus hail fog
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_065.jpg)
Mammatus and Sunset
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_099.jpg)
More Sunset
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_128.jpg)
Lightning
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_143.jpg)
More Mammatus
(http://www.tempestlight.com/reports/My%20Documents/My%20Pictures/Tempestlight%20Print%20Gallery/070207/20070207_156.jpg)
-
Hi all, I have finally had a moment to sit down and post some comments about this day. 7th Feb was a group chase With Dave-wx, Flip, Shane, lil Ben and Ben from South Australia who specially drove over to chase for a few days with us. Thankyou to Michael Bath who has hosted all of my pictures from this day.
The day for me started off from Bathurst with the sky pumped full of accas everywhere at 9am or so after I woke from a late night out chasing south of there. We fired up my one week old laptop and began with a sat picture which certainly showed the Victorian cloud mass from the previous day encroaching on the Goulburn area, which was almost visible to our far SW in amongst left over previous nights storm activity. It was decided we should get going and move north to Mudgee and get another look at the sat picture there. While having lunch in Mudgee congestus was really building up with lots of other unstable clouds to our east. We decided to make haste to Cassilis as road options east west and north were good and gave a reasonable chance to stay with the storm. The trough line was NNW SSE oriented so small cumulus fields were visible just to the west of our target area on the lunchtime sat picture.
After arriving at the Golden Highway intersection with the Mudgee road we proceeded west for about 6kms and found a nice spot to get off the road safely for three cars. Small congestus towers were now clearly visible to our west. These first storms appeared high based but not short on moisture - nice thick anvils persisted all the time. After a while it became apparent that the northern most cell was getting a huge RFB and began to dominate and move forward feeding on the reasonable sfc inflow of about 10knts.
This storm proceeded eastwards and encountered a small range west of Merriwa which IMO could have helped this storm with some orographic assistance. Intensifying rapidly, numerous CGs were now powering and suddenly outflow was visible by a dust plume along the ground in front of the storm. A guster was rapidly forming. One of the cars behind us then yelled in the radio Gustnado! and we all were really excited at seeing one so close!
This storm now began its RFB lowering development near or just east of Merriwa. Lots of turbulent looking areas and heaps of greenage (Vault region). Still once again powerful CGs visible but couldn't linger as we didn't want to get swallowed up by a duster guster :).
Now we proceeded non stop to Scone and at times blasted by severe outflow winds from the storm's NE flank. I started using my A530 out the window in vain attempts to capture a rather well organised storm. After showing these to MB he also commented on a meso/wallcloud like feature amongst them which I had seen in them too.
Now through Scone and heading north to escape any chance of a direct hit from its core we still had to battle severe outflow winds and dust which managed to blow down a small tree and a large branch. Flanking line with pileus leading to the Storm to the right of the frame.
I think the storm was powerful enough to have at some stage an organised appearance and perhaps was long lived enough to be of a multicell at the start and a singular cell for a good part of its passage from Merriwa eastwards. A link of all Images for that day is here:
http://australiasevereweather.com/rodney/photos/2007/rw20070207.html
-
Top stuff Rodney, and the gustnado is just amazing!
Still on this event, I have put a rough cut of video of the chase up at:
http://www.australiasevereweather.com/video/movies/flash_video/2006-2007_stormchasing.htm
Beware it is a very large file, so do consider that before viewing. Unfortunately it does get a tad pixelated at times, I have not attempted to optimise it yet.
Hi Con, yes I guess you have to weigh up the merits of the different areas. There were several possible targets though, for supercells, southern extent was considerably more favourable. Once storms develop it is a question of observing the near storm environment.
-
Great video David - I enjoyed that. That was indeed very impressive rotation and timelapse. How long were you guys onto this cell? Were there any specific variables that could've been better on the day for tipping this cell over into producing a tornado?
-
Jeff, that supercell updraft showing it leaning is quite nice. I recall on your digital camera screen showing the striations a little more. I was talking to David and wandering whether this looked like an "Independence Day" structure. What are people's thoughts?
David the video does well to show the whole perspective of the storm chase from beginning to end. Storm chasers can be a little camera shy I guess haha.
Rodney, great gusnado again and the storm produced some erratic lightning behaviour - great to capture!
Regards,
Jimmy Deguara
-
Great video David - I enjoyed that. That was indeed very impressive rotation and timelapse. How long were you guys onto this cell? Were there any specific variables that could've been better on the day for tipping this cell over into producing a tornado?
Cheers Brad and John, I think we (I) will use video increasingly for chase reporting since writing is too time consuming. Hopefully, Brad, just an 'appetizer' for what you will see in a few months !! I'd say we were on the storm, from the Mt Victoria lookout, if that counts haha, perhaps for 20 minutes and then another 20 minutes or so until will arrived at the location west of Lithgow. Shot video there for around an hour and i'd say another 20 minutes by the time we were back in Lithgow and finished there. Then another 20 minutes or so by the the time the hail had finished - all up between 2 and 3 hours I'd guess.
Tornado - hmmm well the mid-level meso was evidently rather intense. There was decent rotation at the cloud base at times and an RFD notch visible as well at different times. The base was quite low over the terrain. I dont recall us ever being in outflow so can't speculate on the characteristics of the RFD (well temperature and dewpoint). In general, the storm was doing all the right things that as a chaser I have observed with tornadic storms. It just did not happen, well, if it did we did not see it behind 'them hills' east of Lithgow. Paul suggests that there may have been a weak tornado with all the scud west of Lithgow, although being a four eyes I cant say and have yet to check out my video on a larger screen.
Yes those photos are awesome Jeff - that meso photo reminds me of Pampa - Clarendon on May 15, 2003 Jimmy!!!
-
David, Great storytelling of the Lithgow supercell. Still photography is good at capturing moments in time, but for sheer atmosphere in conveying the drama of a storm unfolding , you can't go past video to put everyone else in the picture. Wonderful informative commentary by all on the chase. And Jeff proves again that he is a master at photographing mammatus. Cheers, Con.
-
In my previous posts, I concentrated on the supercell and did not finish the story I guess. Jeff, Matt, David, Paul and I met at my place for a tasty pizza and were greeted to the fantastic sunset.
(http://www.australiasevereweather.com/photography/photos/2007/0207jd81.jpg)
(http://www.australiasevereweather.com/photography/photos/2007/0207jd77.jpg)
Nick had asked what the hell were the photographs showing nothing haha. This is it. It does not do justice as to what we observed going down Scenic Hill - most likely a HP that follows and engulfs the classic supercell.
(http://www.australiasevereweather.com/photography/photos/2007/0207jd65.jpg)
David has it in his video clip.
Regards,
Jimmy Deguara
-
Who said there's nothing in the photos!! Some nice mammatus there Jimmy, great colours to go with it! I'm impressed!
Mike