Topic: NSW/QLD storms 11-12 October 2007

[David C]

Quite unstable air above Sydney right now (10:00am) and some storms are firing over the outer south-west suburbs. I think the lower Hunter will be better positioned with perhaps some more heating going on ahead of the change. Still nice little compact cells firing at the moment are nothing to sneeze at.

[David C]

Warning just issued: 

The Bureau of Meteorology warns that, at 10:05 am, severe thunderstorms were detected on weather radar near Campbelltown and Minto. These thunderstorms are moving towards the east. They are forecast to affect Bundeena, Engadine, the Royal National Park, waters off the Royal National Park and Waterfall by 10:35 am.

Large hailstones and damaging winds are likely.

Golf ball sized hail was reported near Camden Airport at 10 am.

[scottme]

Another rather strong cell has just popped up over Warragamba about 10:30am, looks to be heading just south of Sydney airport.

[David Brodrick]

Further to last night's storm in Narrabri. We had an email from a bloke in town who recorded a 113km/h gust on his Davis weather station. On my drive to work I noticed a colourbond fence blown to pieces, and a caravan had been picked up and dumped about 50m away on the western outskirts of town.

[orage]

The storms are hopeless here. Earlier this morning we had one storm that began to develop out west of here. I have attached this photo that shows the storm before it began disintegrating over Armidale. Not soon after this, there was nothing worth taking. It only lasted half an hour or so. Just now there is another rolling in. There are a couple of rumbles, but I can't see any lightning.

EDIT: That storm passed without consequence. The seems to die over Armidale. Can anyone explain why?

[Stormhunt]

Pretty much the activity firing up in northeast corner now. Nice updrafts out here filling some anvils on top. Hopefully some decent hail, rain and winds. I want some more daytime cg photos as well! ViSat really flaring out of here!  They seems moving very fast though. Lifted Index is -9 today.

[Shaun Galman]

Hi guys,
Looks like another interesting day of weather throughout Eastern NSW. I apologise for not posting these images earlier as I was replacing my uncles TV antenna which blew down in the maelstrom yesterday! The storm was fairly weak as far as lightning, I think we only saw 7 CG at the most, but they were right on top of us by the time the dust rolled in! The wind and dust provided interesting shooting conditions to say the least! 


The storm moving in over town from the West. The fibrous anvil had me a little dissapointed, but the structure looked more "improved" to the NW so we headed off in that direction for a few photos.

The CG were just starting here once that relatively nice base had formed infront of the rain core. We did her the familiar "Jacobs Ladder" sound emanating from the power lines 20feet behind us, time to leave!!! The next shots racing back to the car are self explanatory!


We were stuck in the car for three minutes until we could barely see enough to begin to move, CG were still firing down around us here, very worrying!

The shot above is a few minutes on and facing the opposite direction (East), still too dusty to see our way out!

The local fruit and vege man came out worse for wear in those crazy wind gusts! (looks like he's on the phone to the insurance company lol?)


No much in the way of lightning but the sunet was a stunning after effect of an interesting day!
Cheers guys.
Shauno

[Richary]

Interesting, they have just cancelled the severe weather warning for Newcastle area, but the radar still has lots of nice black bits on it over the Hunter.

[Stormhunt]

Interesting, they have just cancelled the severe weather warning for Newcastle area, but the radar still has lots of nice black bits on it over the Hunter.

Sorry mate, the radar was over-estimated and it hasn't updated since 12 30pm. Storms already gone offshore anyways. Further storms has formed north of Hunter now. Northern Rivers watch out! Storms in west firing up and might bring another natural disaster? Hrmm wait and see!

[Mike]

From looking at the Visat images and the wind profiles around Williamtown other areas affected by these storms the wind speeds are huge.  Satpics of anvils are indicative of the winds aloft - huge, huge rate of knots up there at 100+.  Michael or David, would these winds be supporting the strong updraughts creating the hail?  Also, are these storms supercellular or just 'very' pulse severe?

Mike

[scottme]

Still some very intense cells over Raymond Terrace now.

The northern rivers onslaught is well underway.

[Mike]

I'm sure Michael is out that way getting as much of this action as he can.  Williamtown still has a very nasty storm moving in from the west to them - quite a nice signature on radar.

[Stormhunt]

Those cells are black cores aswell on radar, nothing compared to Newcastle radar! *surprised*
On grafton 128km radar, that cell in my path from sw, have black in it, look like in for hail, hopefully stands this way!

Ed:  No need to push the issue re wishful damage on any town.

[David C]

From looking at the Visat images and the wind profiles around Williamtown other areas affected by these storms the wind speeds are huge.  Satpics of anvils are indicative of the winds aloft - huge, huge rate of knots up there at 100+.  Michael or David, would these winds be supporting the strong updraughts creating the hail?

I think, Mike, the storms today around central NSW are enjoying some modest-moderate CAPE and some good speed shear through the mid-levels and that is helping to promote updraft longevity and probably rotation in some of the more sustained cells. The mid- upper- levels are quite cool and cooling which of course is why hail is occurring with most storms. There were a few storms around (notwithstanding the issues with Lemon Tree Passage radar) that were quite intense and there may have been the odd supercell, but hard to say with any certainty. 


btw, should note that Paul G reported 2cm hail from a cell near Maitland and some close strikes around 2pm.

There are some 'suspect' cells further north around the border region atm. Wind-driven, medium-large hail is a concern up there over the next few hours although the speed shear is very strong, all westerly and all but the strongest updrafts will be flat out surviving for too long --- we'll see.

[Mike]

Thanks for that, David.  From another look at this morning's sounding in that area the front certainly has got some pace behind it, not so good for sustainability but as you mentioned, the speed shear is through the roof.  Those areas affected by large hail will certainly know it. (Probably an apt time to buy a new, but dented, vehicle from the dealerships. Could be a cheap investment on a chase vehicle - the damage is done!)

What is the scenario for the next two days storm wise, one would think with the passage of this trough that you may just get the odd pulse if the instability holds?