Victoria: Rain and Thunderstorm event - August 28th to 31st 2009

Thanks DJ. It's looking fairly promising up til now lets hope it holds.

Hi storms it's possible perhaps on the Upper trough behind as DJ says so might see bit of action Saturday night perhaps

Areas of rain should start to develop from the northwest during Friday and be patchy at first but increase during the day and spread south and east by afternoon to be over the central ranges by Friday dusk. Local thunderstorms about the NW later. Moderate falls building on the ranges and north/west during Friday night.

Saturday will have areas of rain and isolated thunderstorms in most districts, with locally heavy falls mainly near the ranges. Rain tending to showers from the northwest later, with local thunderstorms to follow. NNW winds increasing before shifting SW/W during the afternoon. Isolated hail about the southwest later.

Sunday areas of rain and thunderstorms over the east clearing. Showers, more extensive in central and W Gippsland districts, with local hail and thunder easing during the afternoon from the west. Winds SWly shifting more NWly during the afternoon and strengthening over the west later.

Monday, strong and squally northwest winds will shift cooler gusty westerly from the west during the morning. Showers becoming widespread during the morning the becoming isolated later. Isolated hail and thunder about the coast contracting east later as winds ease.

At this time statewide falls of 10-40mm with more concentrated 25-40mm totals about the divide and in central and eastern VIC.

Well I have been that flat out with homework tonight, its not funny. Only had time to post now.

Personally too this weekend regarding thunderstorm activity, i'd also say along the upper trough with cold-cored thunderstorms, local hail within them again, particularly near the coast. In other words, the prospect of more good rain is great! Will give a detailed forecast Thursday evening! Way too tired now...

Latest 12z UKMet has the low tracking over Victoria just NE of Melbourne which enhances our rainfall chances UK has now pushed rainfall chances of 20-35mm for Central Victoria and Melbourne with a possible inch alone falling between 10pm Friday night and 10pm Saturday morning.
The track of this low will be very crucial if I had to choose I rather it just pass North and East of Melbourne and get the Southern and Western side of the heavier rain than have it move West and South of us and out to sea which will give us less rain I feel for South Central Vic anyway.

12z Laps now inline with other models too with widespread 10-50mm for Victoria and closer to 20-30mm for Central Vic and Melbourne. The 50mm is for the NE ranges.

Model are still holding for Saturday though look to me like they are moving the system through a little more quickly. Looks to me like the rain could be heaviest Friday night into Saturday morning with the SW flow pretty well established by mid-day Saturday. This event has a phenomenal jet - up around 200 knots at 250hPa - so is going to be going at "supersonic" speed.

EC then looks great for next week (though best not to get too carried away ).

Yeah water and land saying pretty good totals around and we are on the boundary of between 10-30mm for the 4 days. I don't mind that model as it seems pretty conservative. I was told they take input from a lot of models and come up with a blend for it. Anyhoo US seems to be thinking something big next week in it's 14 day run. Lots of blue around so we may be (hopefully) be seeing another wet spell just in time for spring and warmer weather that comes with it. If we get that then get your mowers serviced 'cos it will be hard to keep ahead of the grass gorwing. It has been a battle even through the winter up here.

Yeah if I have any concerns of this system is at the speed it is moving million miles an hour but should have enough rain for all of us to get a reasonable drop well at least 10mm anyway.

Yeah next week looking interesting DJ but knowing our luck it will downgrade heaps but something to keep an eye on.

Bom saying widespread 10mm on sat now with NE anything upto 30mm.

Looking like the main models well US and UKMet have shifted the main axis of the rain back North and East with the heavier falls now mainly through the North and ranges still some reasonable falls through Central areas and Eastern Victoria though but little in the SW by the look of things this time round unless they get the showers later.

UK has a wide area of 25mm+ through the Northern Country and parts of the North East not often you see UKMet have such a large area of 25mm+

I think US is slightly underestimating this event given what UK is showing.

LAPS has now shifted the rain south while the other 2 shift it back North slightly. LAPS needs a makeover it is terrible that model always a day behind in these situations. Be interesting what Nogaps, EC & GASP show.

MLaps tends to be between GFS/UK and LAPS scenario but noticing more and more little rain for the South West and heavier falls across the North and ranges. Latest JMA goes against the flow and focuses the rain generally even across the state but especially the South West.

I think its a case of now keep an one eye on the sat pic from now on as well as the sky and models.

So Johnno - North Central should get a fair whack if they're mainly saying north of the ranges and Northern country?

I'm going to go out on a limb Scott cosidering I'm generally a conservative forecaster alot of the time and say 17-23mm for you between Friday afternoon/evening and Saturday could even be more but at the moment I will stick with that mate and I will say 8-15mm for Melbourne at this minute but thats not including the showers behind it. Wouldn't suprise me to see the odd rumble in the band itself as well especially around the ranges.

I still think a Flood Watch should be issued for North East Victoria by the BOM theres a real possibilty that widespread 30-70mm could fall across the North East ranges with this system which will fall on wet catchments already up there places like Eddi Upper & Mt.Buffalo could see falls closer to 70mm

I'm very happy with that! Thanks Johnno.

Looking good in WA now and reckon we are a good chance of at least 10mm out of this. WZ local forecast has 95% chance of 5-10mm, have never seen 95% before so that has to be a good sign!

Cloudband has really begun to take shape in the past 12 hours and should begin to increase in size and precipitation as it gets caught up in the LWT (Long Wave Trough).

I think now there is a good chance of thunderstorms within the rainband which will enter the NW tomorrow this time. The sad part is that it is moving so fast, however it will be a good producer and in the south, showers will be locally heavy with hail and thunder near an upper trough passing behind the rainband.

Melbourne should see 15-40mm across the region. Hopefully everyone can get the 40mm and be on above average for the month!!

Good signs continue into next week.

Reckon there has been a bit of a downgrade on this system. It still looks promising but the good SW'lies after the trough are flattening out. That could drop this from a 20mm+ system to 10mm+ system. Hopefully it looks a bit better in the morning.

Still anticipate ~20-30mm in Ferny Creek for Fri->Mon but wouldn't be surprised to see less any many areas.

BTW could be a few mm's around tonight. The system is scraping along the coast but edging north - may just edge into Melbourne. Both Cape Otway and Cape Nelson are over 5mm for today.

This is a wet August for me, I cant wait for the official figures. They will mean nothing in the over all scheme of things of course.

Latest US has 25-50mm on Fri/Sat for us and 50mm for the sequence here. Not a bad upgrade!!!

Karl Lijnders wrote:Latest US has 25-50mm on Fri/Sat for us and 50mm for the sequence here. Not a bad upgrade!!!

How many is included in "us" Karl??

Mainly central and NE ranges by the looks of things.

I was gobber smacked with more homework tonight, so little time again to write up a detailed forecast for the upcoming event, though I may sneak one in tomorrow evening before much gets going.

Still looking like a very good rain producing system. At this stage I am only expecting little falls with the rain areas, as it should be mostly concentrated north of here, however again it depends on the track of the low. I still reckon we will do well with the showers along the upper trough with isolated thunderstorms as well.

Also, isolated thunderstorms tomorrow developing in the northwest witht the rain areas.

Still looks on track to be a reasonable producer. Should be raining close to Melbourne in about 12hrs.

Most models have 10-30mm for the region.

Looks like the upgrade for the weekend is holding. Latest GFS has widespread 25-50mm falls including for Melbourne. EC and UK even have ~20mm for Melbourne city Saturday which is about as good as these models get

Bit hard to make out today - there is an area of rain on the front to our south and an area of rain to our north. They are both edging towards Vic. Looks like rain initially starting in the NW this arvo and into Melbourne sometime tonight.

Am still anticipating 20-40mm in Ferny Creek (a lot will depend on the period of SW flow we get post low - these can be extremely productive for us).

The only thing that worries me is the gap in the cloudband. Hopefully it fills in as it comes across. I suppose it is only really just startting to develop so I should give it more time. fingers crossed

Should fill with convective rainfall over the coming 12hrs Anthony.

Hope so. I could sunbake out here at the moment