Victoria: First Heatwave of the Summer - 31/12/11 to 3/1/12

[Nick Sykes]

Hey Guys

Looks like the first heatwave of the season will develop over Victoria this weekend and peak early next week. At this stage it looks like the temps will peak in the low 40's on Monday and Tuesday in Northern Victoria (models show 850temps getting up around 24-25).

Hot air looks like residing over Southern Vic as well though temps may be tempered along the coast by a couple of weak sea breeze like changes.

In Melbourne I expect we might see our first 40C of the summer.

It also looks much drier than the last month so I wouldn't expect much in the way of storms.

There is the possibility that the heatwave will extend further than next Tuesday, especially in Northern Vic, the models are having trouble picking the change.

Nick

[Jake Smethurst]

Thanks for getting this started Nick.

I mentioned this a while ago, and yes does appear to be a much drier period approaching. January as a whole seems to be looking more like a hotter month in general. Sunday and Monday are our peak days ahead of a very shallow trough expected to waft across the state either late Monday or late Tuesday, models varying on timing, which means Tuesday could be just as hot across the state as the previous two days. But even Friday and Saturday look hot in the west, though not the peak. And as Nick mentioned, the heat looks like possibly sticking around. It's only a shallow trough, so will only provide temporary relief for southern districts on whichever day it arrives, with some models hinting at the heat returning statewide again on the Wednesday or thereabouts. And we are talking temperatures generally above 30 for the whole state, with most areas likely above 34/35 for a few days, reaching high 30's and perhaps low 40's at times. Going to be shock too, and also low humidities. Thankfully winds are not predicted to be very strong so fire danger is kept not too bad across the state thanks to recent rains; although 'severe' or 'extreme' fire ratings may be achieved on a couple of the days with freshening winds ahead of the shallow trough, mainly western districts, in particular Mallee, Wimmera and Southwest, it's quite dry over the southwest to the moment, not much rain there last few months.

Interesting period to watch.

[johnno]

Yes the humidity won't be as bad its the 1st more intense but more drier heat of the Summer but at this stage (and have for the past few days) can't see it any higher than 37 or 38c at the most for NYD and the 2nd for Melbourne before some sort of trough moves through by Tuesday however it will touch the low 40's in the North West

[Anthony Violi]

Looking forward to it...i think we will cop another caning.

Cant see it being as humid but also cant see it being as dry as the models suggest. I think the models may start to either cradle the trough or wrap it a little once the hot air interacts with cooler air. I think the thing to look at is the following week, if the models are right and they are that slack enormous moisture is going to be sent down this way, dont think it will be this week though. Might even be late Jan.

But definitely looking like a warmer month as Jake said. Good swimming weather if you have 5 weeks off!

[droughtbreaker]

The models are actually indicating significant moisture levels with the heatwave. GFS has precipitable water values 20-30 at the peak of the heat. With 850T approaching 24C max over most of the state you would expect -ve DPs in most years, especially inland, but looking at GFS it should be well into +ve single figures and even touching double figures in the mornings and evenings. GFS can overestimate humidity but the signal is strong. 22C-24C 850T normally translate to temps of 39C-41C at this time of year. This is assuming dry air (which is the norm for northerly wind days in summer) and high 500Ts as well, (500Ts really don't look all that high which could be a limiting factor as well?). OCF only has mid 30s at the highest through southern VIC for the entire event.

We are at the peak of La Nina atm and the moisture levels are high over the continent and potential moisture coming down from the NW is huge. GFS has a very large area of significant moisture flooding the western half of the continent with the next northerly burst (after this upcoming one has passed).

It will be hot sure, mid to high 30s in the south and low 40s in the north and NW, and the RH% will be low purely thanks to the high temps. It will definitely feel quite dry. It is not looking particularly significant on paper though, just a straightforward summer heatwave like we have always had from time to time in the past. There is a definite trend happening for increasing heatwaves over SE AUS both in duration and intensity but it's just something we need to get used to.

[93ben]

Does anyone think we might see what happened on Christmas day again around new years? Because they're showing rain that is forecast just after that and the temperatures are much higher for a long period of time than the temperatures around Christmas.

[Mikew]

The models seem a bit unsure for next week as well
I am going surfing down the west coast next week
If anyone could guage what the winds will be doing that would be appreciated
Hoping the Easterlies go away !

[Anthony Violi]

No i dont think so Ben, we had an extreme airmass and very unstable air in the form of a strong mid level trough. At this stage this system will be far less than that, but much warmer.

However, GFS is starting to wake up and increase the rainfall from Whyndam down to Esperance, meaning its starting to realise it will be tropical air feeding southwards. ACCESS has very moist air so it looks like it may be somewhere in the middle of these two, EC has been atrocious lately so pay no attention to norwegian rainfalls atm.

[Lily]

Yes, what's the go with EC lately? Been way off for the last few months, is there a specific reason for this?

[Anthony Violi]

Yeah, its been fed horse poo..

[Supercellimpact]

Yeah, its been fed horse poo..

and cocaine lol

[Anthony Violi]

Lol...whatever it is, its not doing it any good.

And i turn the news on saying there might be a total fire ban on NYE??? Are these guys on drugs as well?

[Lily]

Media have been beating it up all day (possibility of no NYE fireworks).

[crikey]

Hi Mikew..
Here is a link related to wind direction that should assist you
When you open the link below it will open at the synoptic chart.
You will have to select 'wind direction/speed' from the drop down box and select' generate' button and it will bring up a 7 day wind forecast.
http://www.bom.gov.au/australia/charts/ ... u&model=CG" onclick="window.open(this.href);return false;

This wind diagram is generated by the ACCESS forecasting model.
It is indicating that next Monday 2nd January at 11am the s/west of Vic will be when the change arrives.or in fact has already arrived . The wind arrows indicating a range of wind directions. Could be a little rain / storms ( so take your camera) according to this model at the moment .
Later into Monday evening 2nd Jan 2012 and Tuesday 3rd some s/easterlies as the change pushes into eastern Vic and the next high pushes in. In theory!

**NOTE** Models become less accurate this far out so check on the link a few day before you go to get a more accurate report/forecast

This is another wind model by EC
This wind forecast chart
http://www.bom.gov.au/jsp/watl/wind/index.jsp" onclick="window.open(this.href);return false;
is indicating that Monday 10am a northerly before the change
and some mixed wind direction and unstable wind flow related to the cooler change at 4pm on the s/west coast on Monday arvo
and then a s/.westerly by 10pm
So pretty much both models reckon the change will be in on Monday with some inclement weather
This particular wind model indicates the wetter cooler possibly stormy weather will continue in to Tuesday whereas the previous ACCESS model above indicating Tuesday will be clearing conditions .
By Wednesday some cool quite strong southerlies ( from a new high moving in) should give you some stronger on onshore winds and larger swell l would imagine. according to this model anyway
If l was deciding l would be waiting for change to pass on Monday /Tuesday and go for the southerlies and general clearing on the Wednesday.onwards

Models do update so keep in touch.
Reckon someone will post a new thread on this coming change( around Monday 2nd January) soon
and then you can read in more detail what is likely to happen
regards

l am not a surfer..
Not sure what is ideal for you..for good surfing ? I gather easterlies are no good?

[Rhino]

Heading up to Coffs Harbour tommorow and will be back on the 8th of Jan so will be decent storms/rain around here over that period I'm sure . Nice to know you guys will be getting a few restless nights sleep down here but you'll be right Certainly going to feel it, for this time of the year been real mild imo, and anything over 33-34C is going to hurt. Will keep you posted of what's happening up north although does'nt look stormy at this stage.

Rhino.

[mad*moo73]

Media have been beating it up all day (possibility of no NYE fireworks).

I know, what idiots!!! I LMAO when they were saying it was going to be a scorcher NYE & then said it will be 22 degrees at midnight geez we're all going to be passing out from heat exhaustion!!!! Bloody hell I can remember a few recent NYE's where it has still been 40 degrees at midnight. And yes the fireworks have still gone ahead they always do.

[Jake Smethurst]

Yes not likely going to be a TFB on New Years Eve, just the media hyping up the situation. High to very high fire dangers though are likely, with potentially the 'Severe' category being reached mainly in the western districts on either the Monday or Tuesday ahead of the change with the freshening winds. Models are still diverging with the timing of the change, but does appear to develop through on Tuesday sometime, still to be confirmed on what time it enters the state. But still expected to remain hot following on the Wednesday with some instability returning likely.

[93ben]

Media have been beating it up all day (possibility of no NYE fireworks).

I know, what idiots!!! I LMAO when they were saying it was going to be a scorcher NYE & then said it will be 22 degrees at midnight geez we're all going to be passing out from heat exhaustion!!!! Bloody hell I can remember a few recent NYE's where it has still been 40 degrees at midnight. And yes the fireworks have still gone ahead they always do.

They did mention on nine news that it will still go ahead because the council said if there's a total fire ban they will apply for a special permit straight away. I don't think it will be cancelled at all. 22o at midnight doesn't seem too bad. The only major problem that really affects fireworks is electrical storms and there's none forecast for that night, not even rain.

[aussiestormfreak]

Gday everyone!

Been an EPIC storm season so far, hoping it'll continue right through the remainder of the summer and into autumn

Mixed feelings about the upcoming heatwave, as I've mentioned I don't like hot, dry weather due to the bushfire threat in my area but I'm heading to Corryong early next week, the Bureau is predicting a chance of showers and/or thunderstorms from Monday onwards, which would be a great surprise temperatures around 36C expected in the Upper Murray region during that period, a little hotter downstream in Albury/Wodonga... at least it won't be soaring to 45-46C as it did back in the NYE/NYE 2005-2006 period...

[I_Love_Storms]

I'm a little confused by gfs surface heat maps. I remember looking at these last summer and can't remember such heat all over the country. If these maps are correct, we are only a strong nw away from copping another 45+ day. No matter what humidity and la Nina affecting eastern states, I'm still guessing air very dry in interior. Interested in thoughts of others but it looks like a lot of heat for late dec/early Jan.