Victoria: Heatwave November 7th-12th 2009

Well Things are looking Very interesting for a prolonged period of High heat, starting this weekend, and lasting possibly all the way though next week into next weekend (but that is a long way off).

A Very large and strong high looks to Set up in the Tasman by this weekend and hold there for about a week pumping in Hot and slighlty Humid NE N winds with Temps soaring to High 30s low 40s in the North and Low to mid 30s in the south.
Also aiding with this heat build up is a very large, stable and hot upper ridge, which will allow the heat to just build and stagnate, this will also suppress convection away from the Mountains.

While this heat is normal for November, the not normal part of it is the possible length of it.
North areas may see up to 7 days above 35c and maybe a few above 40c
While in the South Melb could see 5-6 days in a row or more above 30c with maybe a few around the 35c mark.

With the more humid airmass night time temps also will be on the high side with overnights only dropping to the mid to High teens in the south and likely not below 20c across much of the North.

Enjoy the next 36 hours of cooler weather I know I am, things should start to warm up friday and then really start to warm, up by this weekend.

Looks like after 4 years in a row of wet Nov/Decs, it might have stopped with a dry and hot Nov coming up, looks like our wet period was August to early October this year

Summer is most certainly on its way

Looks similar to March 2008... with an immovable anti-cyclone in the Tasman...
It's also worth noting the heatwave of Nov 1980. More than a week of 30degC+ for Northern Vic, and Mildura peaked out at 44.5degC on the 17th! Ouch!
http://www.australianweathernews.com/data/archive/76/1980_11.HTM

Still reckon with the heat pool sitting over the region and increasing moisture in the mid and upper levels, I suspect destabalisation in the form of showers and thunderstorms mainly in the afternoons starting from Monday next week over the divide and then subsequently throughout beyond that in humid NE flow.

Adelaide for instance!!!!

Forecast for Thursday
Fine. Some morning cloud clearing to a sunny afternoon. Light to moderate
southeast winds, fresh about the hills and southern suburbs in the evening.
Moderate afternoon sea breezes.

Precis Fine. Mostly sunny.
City: Min 10 Max 22
Elizabeth: Min 8 Max 23
Mount Barker: Min 6 Max 20
Noarlunga: Min 11 Max 21

UV Alert: 9:10 am to 4:50 pm, UV Index predicted to reach 10 [Very High]
Fire Danger: Low to Moderate (Mount Lofty Ranges Fire Ban District)

Friday Fine. Sunny. Min 11 Max 26
Saturday Fine. Sunny. Min 15 Max 33
Sunday Fine. Mostly sunny. Min 20 Max 33
Monday Dry. Mostly sunny. Min 21 Max 35
Tuesday Dry. Mostly sunny. Min 21 Max 37
Wednesday Dry. Mostly sunny. Min 22 Max 37

Is looking like a shocker in Adelaide coming up, but I think the worst of the heat (beyond 35) will be restricted to on and north of the divide for most of next week IMO, but there may be a couple of days it nudges that close for southern Vic. I am with Karl, I think moisture increases and a trough possibly moving into the area with spark off some storms and showers during the afternoons/evenings from Monday, and I have reflected this in my 7-day forecast in the other thread for some time now. Looks to get humid too!

Strikes me that this won't be that hot in Melbourne. Saturday looks like a sea breeze day, and Sunday/Monday have fairly light winds which again should allow sea breezes. A weak front then comes through on Tuesday and Wednesday/Thursday are easterly. Certainly could see a sequence of mid/high 20s, but I can't see a sequence of 30+C. Am hopeful of the event ending in a big thundery outbreak.... but a long way out.

BUT as you get further west and north the temperature rises and it will be a hot sequence in places like Mildura. This will certainly tip the country from winter into summer quick sharp.

BTW thanks to Blair here is the run down on 30C+ in Melbourne. Just had a look - there is only one instance of 5 or more consecutive 30+ days in Melbourne before the end of November - a six-day run from 21-26/11/1896. Four other instances of 4 consecutive days, only two in the last 100 years (14-17/11/1925, 30/10-2/11/1987).

So therefore we are due for a long run of 30+ days in November.

However the way I see it, as each day goes, it will get progressivly warmer, however as winds will remain quite light, days will be very seabreezy. So for Melbourne for example we may find that bayside suburbs will be coolish, inland suburbs less so. Northern Victoria on the other hand will be and stay very very warm to hot

Sunday looks to be the hottest day in Melbourne Northerly should be stiff enough in my book to see it over 30c, Saturday may be high 20's as Monday but gets tricky after that. All while this is happening should be very hot up North.

I notice the latest EC has 25C+ for us in Ferny Creek for all of next week with no rain. That said there is light northeast to southeast flow for much of the sequence with a trough not far north of us which suggests fairly humid conditions and sea breezes.

It is going to be oppressive further north - hard to see Mildura having a day below 35C in that sequence.

Would not rule out convection and even the odd shower - particularly Mon/Tue/Wed - though at this stage moisture is somewhat lacking.

Yeah quite right DJ.

With the moisture building up literally all around us, eventually it will be advected S into the region and with modest heat about the south and strong heat in the north, this will gradually destabalise the atmosphere and I still think thunderstorms are possible later in the outlook.

I suspect a rain event in about 10 days time with a few thundery days possible leading into that.

Enjoy the last mildish day!!

I will be very suprised if its going to be sunny on all of the next few days as BOM have said... There is a mass of high Jet Stream Cloud out to the WEST, WA and heading into the BIGHT that look like it will hit at least 1-2 days...If that doesnt hit VIC i will be suprised

This is shaping up as a major Heatwave for Inland Vic, SA and NSW with city and coastal folk folk just escaping it by 100km or so.

From about Sunday right though to the end of next week daytime highs will be in the upper 30s to low 40s in the parts mentioned above, which is up to 10-12c above Nov avg for many towns in Vic, S NSW and E SA. Maybe a day or to above is normal. but a possible week with 10c above avg both day and night time temps is big in my books.

Night time temps also look to be only dropping to the low 20s thanks to some humidity and the very still stagnate airmass

For Melb I still think we will see up to 5 days off or above 30c and with the humidity later in the period it is most certainly going to feel warm.
Sea breeze is going to play a big part for CBD and bay side burbs, but more inland burbs should see 30c or more, much of the week starting Saturday.

Shower storm wise, I don't see much early on but from Tuesday or so might be a bit of action around but be very isolated and local, there might be loads of heat and humidity around but that don't mean storms.

Looks like a weak trough might wander around the state next week, but most convection I think will be confined to the divide and very isolated, and I think nothing will occur North of the divide.
Also on some days might see the odd shower and storm form on the sea breeze front a fair way inland both in gippy and central areas

I can only see these temps if the seabreezes play a very very little part in the weather. Low 20's at most tomorrow, mid to high 20's for the rest of the time.

However if the northerlies play a stronger part, then the low to mid 30's on any day is not out of the question. I have said this for a little while now and I stick by it!

Tony

Outlooks easy enough. Warm period approaching, temps near or at or just above 30 for southern regions, above 35 in the north, particularly from Saturday. I still think showers/storms during the afternoons from Monday thanks to the continued moisture build-up and good atmospheric conditions, but mostly restricted to western districts and northeast ranges at this stage closer to the trigger points [trough in west, lift of ranges].

Stratospear wrote:It's also worth noting the heatwave of Nov 1980. More than a week of 30degC+ for Northern Vic, and Mildura peaked out at 44.5degC on the 17th! Ouch!
http://www.australianweathernews.com/data/archive/76/1980_11.HTM

Glad someone mentioned this so that people don't jump to the climate change / global warming reason for this event! LOL

I'd like to think that "Global Warming" has been accelerated since the industrial revolution in the 1920s.

I think a better term would be "Australia drying".

It seems to me that as soon as it starts raining/storming in Northern NSW and QLD that the tap gets turned off here. Then when we get a wet spell that the opposite occurs. Any stats to back that up? or am I just talking crap again?

Perfect day coming up tomorrow. Assuming it rains some time soon, which isn't looking likely.

Bobman wrote:I'd like to think that "Global Warming" has been accelerated since the industrial revolution in the 1920s.

I think a better term would be "Australia drying".

Might have to go a bit further back than that, industrial revolution started around 1800!

Luken wrote:It seems to me that as soon as it starts raining/storming in Northern NSW and QLD that the tap gets turned off here. Then when we get a wet spell that the opposite occurs. Any stats to back that up? or am I just talking crap again?

Perfect day coming up tomorrow. Assuming it rains some time soon, which isn't looking likely.

Luke with my limited knowledge there some basis to that theory. it usually starts raining and getting humid in coastal NSW when highs bring onshore winds to the coasts. This usually happens when the highs are over us, giving us dry stable weather.

On the other hand when the westerlies or south westerlies are bringing us rain, usually means the high is just to our north, bringing dry conditions up there.

Just a very simplified view of it all....I am sure others can explain it better! And I am sure there are exceptions to my analysis!

dagget wrote:
Might have to go a bit further back than that, industrial revolution started around 1800!

Yeah true. I guess I was more inferring the motorisation, aeroplane and coal power plant age.

A chilly start up here today for what looks like the last cool/mild day for a long time (just 5.7C ATM). Looking closely at the models strikes me that we could be in for quite a shock on Sunday with the potential for near 35C in Melbourne (LAPS has 5pm temperatures of around 33C) with possibly enough northerly to hold out the sea breeze. Sunday strikes me as (about) the hottest day in the south with the northerly dropping out for most of the next week and being replaced by light NE to SE winds. Of to the beach for the weekend so looking forward to the warm

Next week is looking increasingly interesting with good mid level moisture slowly drifting down over the southeast in a persistent SE to NE flow. The main problem is the thumping upper high which sits over the southeast with 850T into the teens. The EC starts to put patchy showers across Vic from Tuesday onwards - looks to be isolated, but should give us something to watch and there is always the chance you might get lucky

Of course, move inland a bit and it is going to be one long hot week...

Glad someone mentioned this so that people don't jump to the climate change / global warming reason for this event! LOL

- thing is that we know that Australia (and the globe) has warmed by about 1C and the oceans have warmed around us by about 0.7C. That means every single hour, day, week, month and year in our lives is impacted by climate change. It is not a matter of this cold day disproving global warming or a hot day proving it - the atmosphere feels this extra heat every single day and it is an inseperable part of the system. BTW one tid bit I'm watching - if the models are right November 2009 has the potential to be Australia's hottest on record.

Bobman wrote:

dagget wrote:
Might have to go a bit further back than that, industrial revolution started around 1800!

Yeah true. I guess I was more inferring the motorisation, aeroplane and coal power plant age.

Thats very true, though I would identify the period immediatley post war as cars became much more avaliable and cheaper for the masses. If we are long term CO2 impact, coal was king in the 19th century and steam ran pretty much everything industrially so industry was a massive producer of CO2. I guess I was thinking about the start point of human produced CO2 emissions over the longer term.

Quite right, dagget. I'm on the fence like many on the issue, but I do believe that there is only good things to come from reducing emissions in the air we breathe, especially the potential to reduce the impact of some cancers.

Being stuck in traffic or riding a bike with old smokey cars around you is not that great on the lungs.

Clear blue skies here in Moorabbin and it's quite nice outside. Great day to be out in the garden or for a walk to the park.

will be nice, until the seabreeze kicks in and it gets all cold again!

Tell you what guys I actually want it to get hot..damn hot, hope that seabreeze does not make it over the ranges and we get 35 degrees plus.....only because my newly refilled hot tub has no heater and makes a great plunge pool and I have been waiting all winter to try this out...

I don't see you having a problem with that Daggert.

No seabreezes or cooler winds will penetrate up that way!

Here on the other hand will see the battle wage between seabreezes and warmer winds.