Victoria: A week of fronts/lows for SE September 21st-24th 2009

Page 13 of 15 Previous  1 ... 8 ... 12, 13, 14, 15  Next

View previous topic View next topic Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  norfolk on Wed Sep 23, 2009 4:36 pm

very similar here, with out the shower/drizzle. And yes the sun was pleasant away from the wind.

norfolk

Posts : 413
Join date : 2009-05-19
Age : 42
Location : Caroline Springs

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  droughtbreaker on Wed Sep 23, 2009 4:51 pm

Came home to a few decent showers but only very brief. Was intense enough to put the wipers on third click though.

Friday to Monday certainly does look pretty crazy. Heaps of moisture with it right through if the models are to be believed. GFS has around 15mm or so for here on the weekend coinciding with all the cold air, that's after around 15-20mm on Friday. Normally with SW gales around a low we don't do very well here but it's all systems go with this one by the looks of things.

How low do you think the snow will get Saturday night/Sunday David? With -4C 850T surely I'd be looking at a chance at my place (520m asl). The higher parts of Mount Macedon should be a whiteout by Sunday, I don't think we've had anything this promising for a long time with the rainfall and cold air actually appearing together. Also in spring we tend to get sharper drops in temps in showers than in winter (latent heat?) thanks to more energy available generally with stronger sun and radiation heating building better, more intense showers basically and you can get snow at higher temperatures, a few degrees above 0C sometimes if the showers are particularly intense.

droughtbreaker

Posts : 640
Join date : 2009-05-17
Age : 35
Location : Mount Macedon (520m asl)

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  hillybilly on Wed Sep 23, 2009 5:49 pm

How low do you think the snow will get Saturday night/Sunday David? With -4C 850T surely I'd be looking at a chance at my place (520m asl).

Main thing that worries me is the temperatures. It is pretty marginal with thickness values dropping to about 532. That should see flurries down to 500m (but doesn't leave much margin for error). The vigour of the airstream and the very strong cyclonic curvature (missing Tasmania) suggest we should get some thumping showers. Vigorous showers training can also lower the snow level which is in our favour.

Personally, I'd say snow about the tops of Macedon and Mt Dandenong is highly likely - at our elevations certainly should see some sleet and graupel but touch and go for snow - certainly would not be expecting it to settle. Really will be watching the progs closely the next 36 hours as the coldness of the air is better resolved.

PS Spring can throw up surprises - we had snow up here on GF day in 2003 and then had another fall two days later which accumulated to nearly an inch. That second event came with a cold pool marked at 536 so you can get lucky.

hillybilly

Posts : 742
Join date : 2009-05-18
Location : Ferny Creek

http://www.bom.gov.au

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Twister on Wed Sep 23, 2009 6:37 pm

Great week so far
Mallee has done really well with 20-75mm so some massive falls up there
SW has also done well with 20-40mm falls
All along the Murray have done well to with 20-40mm
NE had some good totals and some miss out
Central done around 15-30mm which is solid to

Fri-Sun looking Great. Should see easy another 20mm around here, easy 40-50mm in hills and dams up to 70mm would not surprise me in parts of dams and hills.
SW should see another 20mm or so, so to should the NE another 20-40mm with up to 30-40cm of snow on the Alps more great news for runoff.

On and South of the rangers should have a great 48 hours from Midday Friday till Sunday avro looking Cold Windy and Wet, classic winter weather should be great.

North side of rangers see about 3-10mm not much more than that, Wimmera may see up to 20mm in parts but that about it

Cold windy few days with lots of showers hail and thunder

Twister

Posts : 80
Join date : 2009-07-01
Location : Notting Hill

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  JC on Wed Sep 23, 2009 6:37 pm

With 850 temps at -4 and thickness levels @ around 532 I would have thought snow down to around 1000/900 metres is more likely HB?

With mt Dandy Summit at 633 and Mt Macedon at just over 1000 metres I think it is very hard to compare the two..
My thoughts are that Mt Macedon has a far superior chance of snow.. I predict Friday night into Saturday morning as the best chance for Mt Macedon as the cold pool migrates east and the winds swing from North West, through to a more westerly trajectory.

Once things go more westerly and ultimately south westerly I would think that the Dandenongs will have their best shot as the long distance over land tends to dry out precip and it struggles to reach Macedon.
However I personally don't think this one will be quite cold enough for the Dandies and I would assume sleet at best.
Maybe the odd flake in a solid coldie downdraft.

Happy to be corrected here.

As a side note that ECL almost looks cyclonic at the moment.

JC

Posts : 15
Join date : 2009-06-30

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  hillybilly on Thu Sep 24, 2009 5:14 am

With 850 temps at -4 and thickness levels @ around 532 I would have thought snow down to around 1000/900 metres is more likely HB?

JC -4 850T means a temperature of (about) -4C at 1200m. With a lapse rate near 10C/1000m which is usual for cold outbreaks that puts the freezing level near 800m. Snow will usually fall 200 to 500m below the freezing level (depending on the vertical temperature gradient, intensity of showers and humidity). That would put the snow level on the weekend somewhere between 300 and 600m.

It's a bit of an art predicting snow levels as the mesoscale strongly controls the snow levels. Last August - for example - the persistent of the precipitation lowered the snow line in the Dandenong to 100m with snow falling into Boronia. and settling at around 200m At the same time I know people further south above 300m who saw no snow and just rain.

My experience at 400m is that -4C (about 532) is pretty marginal and more likely to give sleet. At -5C (about 528) snow is almost certain and -6C (about 526) will produce good snow for us. I have seen snow settle at our place in thickness values of 536, and in July 1995 there was actually a day when it snowed for nearly 24 hours with a thickness value of 540.

(PS you are right that this Mt Dandy and Macedon are different heights but in the situation I suspect both will see some snow).

hillybilly

Posts : 742
Join date : 2009-05-18
Location : Ferny Creek

http://www.bom.gov.au

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Karl Lijnders on Thu Sep 24, 2009 5:16 am

Plenty of showers about this morning with a significant line in the southwest. Could be an interesting day and EC could be right afterall with 5-10mm today.
avatar
Karl Lijnders

Posts : 1472
Join date : 2009-05-17
Age : 33
Location : Knoxfield, Victoria

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  hillybilly on Thu Sep 24, 2009 5:21 am

Looks to me like the EC model is on the money today with it's predictions of heavy showers across southern Vic (http://www.yr.no/place/Australia/Victoria/Mount_Dandenong/hour_by_hour.html). Up to nearly 20mm at Mt Gambier and some nice heavy showers moving across western Vic ATM.

Was cool and drizzly in the Dandenongs this morning

Reckon the band near Mt Gambier is worth watching for storms as it moves across Vic with increasing solar heating Very Happy

hillybilly

Posts : 742
Join date : 2009-05-18
Location : Ferny Creek

http://www.bom.gov.au

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  firestorm on Thu Sep 24, 2009 5:37 am

just some light drizzle overnight again but looking at the radar a band of rain is not too far off if it dosent break up over the rangers fingers crossed for the one. Otherwise a moderate NW wind and mainly overcast.

firestorm

Posts : 128
Join date : 2009-06-13
Age : 33
Location : Aireys Inlet

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  JC on Thu Sep 24, 2009 6:06 am

hillybilly wrote:
With 850 temps at -4 and thickness levels @ around 532 I would have thought snow down to around 1000/900 metres is more likely HB?

JC -4 850T means a temperature of (about) -4C at 1200m. With a lapse rate near 10C/1000m which is usual for cold outbreaks that puts the freezing level near 800m. Snow will usually fall 200 to 500m below the freezing level (depending on the vertical temperature gradient, intensity of showers and humidity). That would put the snow level on the weekend somewhere between 300 and 600m.

It's a bit of an art predicting snow levels as the mesoscale strongly controls the snow levels. Last August - for example - the persistent of the precipitation lowered the snow line in the Dandenong to 100m with snow falling into Boronia. and settling at around 200m At the same time I know people further south above 300m who saw no snow and just rain.

My experience at 400m is that -4C (about 532) is pretty marginal and more likely to give sleet. At -5C (about 528) snow is almost certain and -6C (about 526) will produce good snow for us. I have seen snow settle at our place in thickness values of 536, and in July 1995 there was actually a day when it snowed for nearly 24 hours with a thickness value of 540.

(PS you are right that this Mt Dandy and Macedon are different heights but in the situation I suspect both will see some snow).

Good morning Hillybilly.

Your working above are not dissimilar to my understanding and I am well aware that your knowledge is far superior.
I was always under the impression that the approximate height of 850hpa is around 1500metres above the surface though?
So 1500 @ -4 minus (around 1degree per hundred metres I know that it gets more technical than this) gets us to a freezing level of around 1100 metres. I know snow can fall well below freezing levels hence my lower estimate of 1000/900 metres.

Why is your 850hpa height stated as 1200m?

Cheers in advance.

JC

Posts : 15
Join date : 2009-06-30

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  hillybilly on Thu Sep 24, 2009 7:07 am

Your working above are not dissimilar to my understanding and I am well aware that your knowledge is far superior.

Johnno the 850 level varies with the surface pressure and the temperature - I took a guess at what the current progs were suggesting. Looking closely the actual level looks to be (about) 1300m at the peak of the cold outbreak over southern Vic.

If you look across southern OZ on Saturday the level ranges from near 1200m over Tasmania to near 1600m over southern WA.

The variation of the levels is a bit of a trap for "young" players. I've seen 850T before to -7 associated with BIG highs coming in behind cold outbreaks. These look furiously cold, but when they are sat at 1700m (rather than ~1300m) they are a pretty unremarkable airmass!

I actually find the thickness values a better guide on most occasions as they measure temperature and are not dependent on surface pressure.

hillybilly

Posts : 742
Join date : 2009-05-18
Location : Ferny Creek

http://www.bom.gov.au

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  I_Love_Storms on Thu Sep 24, 2009 8:56 am

It's looking alright over the city, but of convection around maybe...should get 1-2mm out of this band.

I_Love_Storms

Posts : 445
Join date : 2009-08-06
Location : Lilydale

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Power Storm on Thu Sep 24, 2009 9:11 am

Yes it's quite a heavy band of showers moving through, and I can tell you I thought all hell was breaking lose outside, I totally forgot about what EC had been saying, so I got a nice suprise Razz Yeah DJ, should watch that shower as it progresses eastwards and it gets some solar warming into it, might get some thunderstorm motion about it. I suspect to see a few more showers develop this afternoon across southern Victoria, with thunderstorms possible as well, mostly along the southwest at this stage where the most intsability sits IMO, but the chances are spread through much of the south. Laughing ...


Last edited by Power Storm on Thu Sep 24, 2009 9:50 am; edited 1 time in total

Power Storm

Posts : 703
Join date : 2009-05-18
Age : 24
Location : Simpson South

http://www.australianweathernow.yolasite.com

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  I_Love_Storms on Thu Sep 24, 2009 9:47 am

Nice little squall line!

I_Love_Storms

Posts : 445
Join date : 2009-08-06
Location : Lilydale

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Sniper on Thu Sep 24, 2009 10:12 am

Belting down in all directions in CBD.
Nicely predicted DJ cheers

Edit: Whiteout conditions..Love it!!!!

Sniper

Posts : 652
Join date : 2009-06-12
Age : 40
Location : Doncaster East - 133 asl

http://www.stubbysolutions.com.au

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  floydlove on Thu Sep 24, 2009 10:17 am

DJ, on the money again. It's pouring!! Absolute white out conditions.

floydlove

Posts : 141
Join date : 2009-08-08
Location : Melbourne, Inner-East

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  I_Love_Storms on Thu Sep 24, 2009 10:20 am

Yep agreed, pouring here in Camberwell.

I_Love_Storms

Posts : 445
Join date : 2009-08-06
Location : Lilydale

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Sniper on Thu Sep 24, 2009 10:23 am

Melb up to 5.4mm.
Sweet as!!

Sniper

Posts : 652
Join date : 2009-06-12
Age : 40
Location : Doncaster East - 133 asl

http://www.stubbysolutions.com.au

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  I_Love_Storms on Thu Sep 24, 2009 10:23 am

Gee, that was quick

I_Love_Storms

Posts : 445
Join date : 2009-08-06
Location : Lilydale

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  floydlove on Thu Sep 24, 2009 10:24 am

A lot of people wrote today off, I'm loving this. White out conditions for a good 10 minutes now, I'll probably get a quick 10mm. Smile

floydlove

Posts : 141
Join date : 2009-08-08
Location : Melbourne, Inner-East

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Melbourne Skywalker on Thu Sep 24, 2009 10:30 am

It's not everyday that you see the city topping the rainfall totals. Look at that cell grow on the radar as it heads east. Some of you guys out there are going to get smashed.


Last edited by Melbourne Skywalker on Thu Sep 24, 2009 10:35 am; edited 1 time in total

Melbourne Skywalker

Posts : 154
Join date : 2009-06-17
Location : Burnside Heights

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Johnno on Thu Sep 24, 2009 10:34 am

49mm for the City now for September which makes it the wettest month all year there. Heavy downpour around Vic market until 15 mins ago got told my a friend working thee

Johnno

Posts : 741
Join date : 2009-05-18
Age : 40
Location : Near the Showgrounds

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  I_Love_Storms on Thu Sep 24, 2009 10:36 am

And about 4 times the Sept rainfall from last year (I think it was 12mm)

I_Love_Storms

Posts : 445
Join date : 2009-08-06
Location : Lilydale

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Dez on Thu Sep 24, 2009 10:42 am

Why is the humidity in Avalon so low compared to all the other places? Shocked

Dez

Posts : 84
Join date : 2009-07-22
Location : Taylors Lakes

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Australis(Shell3155) on Thu Sep 24, 2009 10:46 am

3mm in a matter of minutes.. I think i could see some hail on the sky light.
avatar
Australis(Shell3155)

Posts : 166
Join date : 2009-06-12
Location : Boronia

Back to top Go down

Re: Victoria: A week of fronts/lows for SE September 21st-24th 2009

Post  Sponsored content


Sponsored content


Back to top Go down

Page 13 of 15 Previous  1 ... 8 ... 12, 13, 14, 15  Next

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum