Cold Air Collision Low - June 5-7th

[Storm Struck]

Looks like an interesting week showing up on the models for next week, a northern Tasman low comes down the country while a very cold blast comes up from the south should these collide it could be interesting.
Theres also a low sticking around NSW that might come across too maybe more the North Island and hit the polar outbreak into late Thursday, still a fair way out but might well be some start to winter for many.

[Talbotm]

Just looking at metvuw heard on the radio theres possibility another reasonable snow could be on the way for 5th june next week. Definitly has the right mixture with some moist northerly flow in it as well as a good undercutting southerly. Just depends on whether it stays southerly or goes more SW but it looks as though it could be swinging SW at the moment but still abit of time to go yet. I think Avalanche got in the early call on this one if it happens.

[mikestormchaser]

Interesting to hea bout next week's snow chances, sounds good, but along way out yet as we keep saying all time lol
Certainly something to keep eye on.

[borris89]

Metservice now has snow to 200m in Southland, occassional snow for Queenstown and snow in the hill suburbs from Dunedin this Tuesday.

[NZstorm]

Metservice now has snow to 200m in Southland, occassional snow for Queenstown and snow in the hill suburbs from Dunedin this Tuesday.

Looking like a warm advective snow event for the South Island Tuesday into Wednesday. Snow could fall as low as 100m so worth watching to see how this shapes up. Foothills of Canterbury look most in the firing line.

GFS chart for midnight Tuesday showing huge temperature contrast at 850mb over the SI!

[CHCH Weather Chaser]

Interesting system coming up on Tuesday into Wednesday. GFS isnt picking up how cold the air is going to be in terms of thickness due to the 'warm advection' scenario. Hopefully timing will be great with the 2 systems colliding and therefore snow level will lower a lot more than the models pick up?

Tony from Blue skies has an interesting forecast for the Canterbury Plains. "Expect around 20cm of snow accumulating above 200m, and 3-5cm to sea level". Metservice have the snow level to 300m but in there extended outlook have snow to sea level in south and east of SI.

Anyways looking like this system will bring more interest than the whole of May did here.

[Storm Struck]

I thought this now warrented its own new thread ive been watching it on the models for the past week or so and its still looking like a reasonable event for many areas from Otago up to Marlborough.
A very cold southerly surge collides at the right time with a northern Tasman Sea low, some models pick more than 30mm for some areas of Canterbury while others abit less.
So this would be a snow advective event to an extent, right down to sea level but inland areas would more than likly get the majority of the snow.
First belt for winter roughly 6 days in cant complain really unless you dont like the cold , might be a good excuse to get out there and stock up on the wood and food etc just incase it turns into a large event.

[Tornado Tim]

Thank you Jason, I was hoping someone would make a new thread other than me, LOL

There is potential for some cold storm activity too as the warm and cold air collide,will be a bit more certain on this later on.

[spwill]

The ECMWF has been vey good, it picked up on this possible moisture/cold air collision over a week ago.

[Avalanche]

Yes i have to agree with you spwill it did. i been watching this for nearly a week my self it seems to be getting worse as the week progressed almost a snowstorm like 2004 possibly. When cold and warm collide all hells breaks loose. Will watching with excitment hopefully it moves north a couple of hundred km. Alot of snow could fall from this event me thinks.

[TonyT]

GFS also modelled very cold air from about 10 days back, although fluctuated on the moisture. Looks like a fun week for sure, just a question of where and how much.

[CHCH Weather Chaser]

I see your going for 20cm to sea level in Southland Tony.

[mikestormchaser]

hmmm very exciting indeed! Dont think it will change much " hopefully" in the next 48 hours, certainly sounds awesome!! Yes Tony that is the question.. where and how much. as we never really know to be honest.
The weather plays all sorts of tricks.. somestimes it says we " sea level" wont get anything, then all of a sudden we have 20cm on the ground. very unpredictable, this will be exciting to see what happens

[Richard]

Thanks goodness i brought in some extra round bales of hay for our sheep

[CHCH Weather Chaser]

Dont think it will change much " hopefully" in the next 48 hours, :

The GFS has been very consistent over the past 36 hours or so with this now.

[Talbotm]

Well done avalanche you spotted this last week. Looks to be a very unstable mix just hope it tends southerly rather than going south west. Fingers crossed i see met service are finally coming round to the idea there could be something in it.

[Avalanche]

I havnt got much time today but can someone put some picks up of the latest GFS thicknesses would be awesome cheers

[CHCH Weather Chaser]

I havnt got much time today but can someone put some picks up of the latest GFS thicknesses would be awesome cheers

They don't look impressive at around 530 at the lowest but it won't be taking into account the warm advective scenario. Wouldnt be reading much into those for this one...

[Thunder]

The high south of Australia has always been fairly far south in these models runs to so sort've helps to back up this situation.

[Avalanche]

The high south of Australia has always been fairly far south in these models runs to so sort've helps to back up this situation.

Yea totally agree, the further south it drifts the HIGH it would give an even better chance of straighter isobars to NZ providing another high doesnt develop above NZ. 540 thickness i guess will have to wait and see what happens here.

[CHCH Weather Chaser]

High risk for heavy snow in northern Otago and Canterbury on the severe weather outlook. "The heavy snow expected in the north of Otago and Canterbury has the potential to cause major disruption" (metservice(

[Chris Raine]

Waitaki Civil Defence has issued a snow advisory to its Rural Support trust advisor and placed its CD personnel on watch

[mattyj46]

Ahhhh its times like these I wish i still lived down south, oh how I will miss the winter

[CHCH Weather Chaser]

Latest run has backed preciptation off for Canterbury. Hope it changes back

[snowstormwatcher]

Latest run has backed preciptation off for Canterbury. Hope it changes back

Yes GFS Was showing 40mm here now just 11mm.
But I wouldn't pay much attention to GFS rainfall as it changes way to much to take seriously.