Central NSW Storms 6th - 8th Feb 2007 - Lithgow/Mudgee/Scone Supercells

[David C]

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  :

[Michael Thompson]

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.

[Jeff Brislane]

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.

[Michael Thompson]

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.

[Michael Bath]

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.

[Mike]

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!

[David Brodrick]

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

[David Brodrick]

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

Please do not post links to WZ forums. You may mention them but no linking.

[Jeff Brislane]

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.

[David C]

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


more impressive


better still




what the....


weakened a little and reorganised and base lowered



Heading east towards Lithgow...beaver tail ahead


multiple inflow bands and beaver tail meet the supercell base


At Lithgow, storm above was VERY impressive now (needed fish eye lens but video will be amazing






beaver tail / updraft base interface


rotation was even more incredible here. Jeff has a shot looking north at what was above us


hail begins falling from the vault above us


we copped a hiding from this giant hail - 6cm measured and which Jimmy reported to the BoM



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.


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.

[Jimmy Deguara]

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.









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

[Paul Graham]

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

[Rodney Wallbridge]

Hi all - some photos of the storms during yesterday's chase from Mudgee to Scone.

[Rodney Wallbridge]

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.

[Michael Bath]

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 / Lifted Index

Relative Humidity: 0300 / 0500 / 0600 / 0700 / 0850 / 1000

Temperature: 0300 / 0500 / 0700 /  0850 / 1000

Winds (knots): 0200 / 0300 / 0500 / 0600 / 0700 / 0850 / 0925 / 1000



Interactive radar loops for 7th February

Kurnell 128

Sydney 128

Sydney 256

Newcastle 128

Newcastle 256

Newcastle 512


Regards, Michael