Victoria: Unsettled - 14th-16th December 2010

[Supercellimpact]

Since they is no thread for this cold front and assiociated trough here is one. It looks to fire up showers and few storms with cape of 900 along the front and cape of 1400 torwards the east of Melbourne and the north east of Vic. But timing will have to be watched to get a good trigger. Shear is great, but we will have to wait and see what pans out.

[Flangfest]

A storm would be a great birthday present! Lets hope all the elements combine to deliver some activity.

[Lily]

Norwegian's suggesting 30mm for my area next Wednesday, GFS just 1mm!

[Karl Lijnders]

Wednesday is the wild card system but then next weekend looks a little nasty and falls of 50mm possible across some parts of the state. By then, hopefully without Wednesdays rainfall, things might have eased in communities. But the turn around between major rainfall systems are just outrageous. We have turned sub tropical with rainfall too match!

[Didjman]

A storm would be a great birthday present!

Same here!! I will be 21 for the 30th time lol
Peter

[johnno]

Latest 18z GFS throwing up better numbers for mid week

[Supercellimpact]

Yep, a midweek storm day. Might get a severe storm or two. Have to see what gfs says it the next 2 model runs.

[Anthony Violi]

Wouldnt worry about GFS...i like this system, has a nice upper trough.

So at least 25mm, depending on moisture advection ahead of the system.

Then its party time after that as we introduce winter again to Melbourne.

[Karl Lijnders]

Wouldn't read too much into Norweigen either. Models are useless this far out it seems.

[damiantheomen]

yeah karl norweigen went from 40mm now down to 2mm fair variance i'd say!

[Anthony Violi]

Yes, it looks like the whole system may dive south too far, though we should still see a little moisture interaction.

Upstream, thing looking decidely good for next weekend.

[droughtbreaker]

Next week looks pretty tame to me. The system in question is a very weak one and moisture levels are not there. It actually looks like a dry change to me in central areas. Showers and storms should form in the east with some modest totals.

Next weekend is still up in the air. Most of the models are not interested in this stage. There will be rain but nothing significant.

[Jake Smethurst]

As for the midweek system. I have just checked out the models (did not see them past few days due to internet troubles) and generally does not look like that much of a system. Quite tame as Andrew says, just a trough feature expected to mostly have an impact on eastern Victoria where moisture levels are better and where it moves through at a prime time ... the afternoon.

Should see some scattered showers along the trough/front line itself over western and central Victoria, easing back to isolated showers following the system and it all seems to clear out pretty quickly too. Eastern parts will see scattered showers and isolated thunderstorms with the change.

After this, weekend system is still in the air too IMO. At this stage, I am just expecting some scattered showers to push through with not much else. Does not look very strong either. Temperatures will be cooler though, but I don't think too cold ... high teens in the south, low-mid 20's in the north following the system.

I would be looking further out closer to Christmas to see something more significant in the way of rain and storms. Something is brewing around then, with warmer temperatures returning as well ahead of it.

[Anthony Violi]

I disagree...i think moisture is the least of the worries. In fact i think we may see an upgrade on Wednesday, models arent reading things to well IMO.
We have an upper trough, mid level disturbance, and moisture already feeding into the disturbance from the indian ocean. And also you can see the invisible moisture in Wa when convection goes up this arvo..could change but thats how i see it.

And next weekend we are going to get one of the great spankings of recent times, at this stage at least. Im not interested in models, all that interests me is the enormous surge of cold air from the due South. Thermal gradient will be extreme, models will jump all over this at the last minute. The only question mark about this is the TC..if it is as strong as GFS is suggesting due to the very warm Indian, it will fan moisture SE and we will see another flood event.

BTW..check the water vapour, and you will see we have tonnes of moisture that will unleash on us.

[Karl Lijnders]

I disagree...i think moisture is the least of the worries. In fact i think we may see an upgrade on Wednesday, models arent reading things to well IMO.
We have an upper trough, mid level disturbance, and moisture already feeding into the disturbance from the indian ocean. And also you can see the invisible moisture in Wa when convection goes up this arvo..could change but thats how i see it.

And next weekend we are going to get one of the great spankings of recent times, at this stage at least. Im not interested in models, all that interests me is the enormous surge of cold air from the due South. Thermal gradient will be extreme, models will jump all over this at the last minute. The only question mark about this is the TC..if it is as strong as GFS is suggesting due to the very warm Indian, it will fan moisture SE and we will see another flood event.

BTW..check the water vapour, and you will see we have tonnes of moisture that will unleash on us.

I tend to agree.

[droughtbreaker]

I think moisture levels are the major factor at this stage. Wednesday is looking dry and the trough is diving south and weakening. North eastern VIC always gets the better of these sort of systems with the topography of the alps and usually a better moisture feed as it is closer to the east coast and often retains residual moisture that central VIC doesn't if a drier NW airstream comes through.

Next weekend there certainly looks like a significant system coming through, not questioning that, what I am questioning again though is moisture levels. The cold air comes in quickly and as we know, cold air carries less 'precipitable water'. Not saying it is going to be exceptionally dry or anything, it will actually be quite a moist airstream in terms of relative humidity but the potential just isn't there for a big event that causes widespread flooding, like we have seen so many of over the spring and early summer. It is more of an Autumn/Winter type system.

It will be very unstable. There are likely to be showers developing with local thunder and small hail. East of Melbourne should do pretty well with the fairly warm bay along with South Gippsland and coastal regions (probably 20-30mm with local higher falls), but many places, particularly inland are not likely to see big falls, only 5-15mm at this stage. It is more of a standard December front and low than the La Nina deluges we have seen for the last several months. Most parts will not see flooding from this as the high totals will not be statewide.

[Anthony Violi]

I have a feeling we may see a very decent thunderstorm event on Wednesday. One of the reason the models arent going for totals.

Looks like a nice convective set up.

[Jake Smethurst]

There are some signs starting to show, albeit very weak, that there could be late shower and even a thunderstorm in the west on Tuesday. Will be keeping an eye on that.

Wednesday to me only looks like favouring the eastern half of Victoria for thunderstorms in my opinion, where the better moisture is and where the trough is expected to move during the afternoon. For much of the western and the central district, the system moves through at the wrong time, and is only likely to produce scattered showers.

The weekend is looking more interesting, with showers and isolated thunderstorms developing in the west later Friday. However I still think scattered showers at best for the remainder of Victoria on Saturday in a deep southwesterly fetch. Cooler temperatures, but nothing we have not seen before in December. The weekend is looking like a more traditional front as Andrew mentions. Don't really think at this stage we will see big falls.

Still watching the Christmas period ... looking very interesting.

[I_Love_Storms]

We had a similar cold outbreak around the same time last year. Most likely some very nice cold air instability. Eastern burbs, especially the dandenongs, should do well on the weekend.

[Monbulkian]

Just had a look at Norwegian. Has 0.5mm for us on Wednesday but 40mm for us in the next week, most of that falling on Sunday and Monday. Is this a model that is accurate? It always seems to under forecast the rain up here for us. Admittedly I'm new to all of this and don't often look at it's forecasts this far out but it happened to catch my eye.