Deepening low prediction/ cold outbreak Mid June

[Lawrence]

Looks like the South could get some fairly bad weather at the start of next week with a fairly cold upwelling and associated low developing off the East coast of the South Island.(In Jeramy Clarkson Voice) "Classic"

[Storm Struck]

I have been watching this low system very pleasently show up on most of the models, as it wraps back in towards the east coast.
It is a little early to say but since you started this topic already, GFS does look good for very low level snow on Sunday/Monday across much of the South Island.
Still more of a sit on the fence situation at the moment, but after a milder week people could be suspicious of a cold blast coming.
This is what Snowforecast website shows for Monday.

nzsnow132_9884.jpg

[gllitz]

Here we go, again...12Z model run for GFS certainly is impressive, but will change/evolve...only second time anything has shown up on it. Still too far out to call, though. NOGAPS and ECMWF show almost nothing at all happening, so I am a bit wary of anything...

[CHCH Weather Chaser]

Yes, i agree with all of you in some way. Gfs this morning shows very favourable snow with good amounts where as MS 7 day maps does not tend to show this. I have attached the set up below.

[NZstorm]

gfs 00Z hints at a good dumping of snow for central North Island early next week due to a Tasman Sea low crossing and running into the cold air coming up from the south. But thats just model output at this stage, not a forecast.

[Storm Struck]

I am still abit uncertain as to what could happen from Sunday-Wednesday, but certainly now that we are a little closer we should be starting to get an idea from the models etc.
Some GFS runs ive looked at now want to bring a rapaidly developing deep low off the coast near Dunedin to around 972hpa, all we need is for the low to swing in abit closer and it sure will be a rough ride.
It certainly will be cold enough for very low level snow 200-300m, but there also could be some beafier type showers which would possibly bring down those freezing levels as we know it can well do.
3 years ago today in Rememberance of June 12th Snowstorm .
Thoughts people.....

[gllitz]

Still too early to call...NOGAPS and ECMWF not even showing a thing...

EDIT: most recent GFS run attached for CHCH...looks more impressive over the southern half of the SI...but still too early to call, as said above...NOGAPS and ECMWF still show nothing significant happening, really...we'll see over the w/e...

[NZstorm]

yes, GFS has a potent winter system moving across Southland/Otago Monday/Tuesday timeframe. If that scenario was to come off it would bring decent snow to sea level for southern regions. However UKmet is currently not in agreement although it does have a strong system in the southern oceans south of the South Island on Monday.

[CHCH Weather Chaser]

Looking quite nice atm!

[NZstorm]

12Z gfs still indicates sea level snow for the lower South Island on Monday and ukmet falling into line on this. Dunedin should get snow to very low levels Monday.

[Lawrence]

12Z gfs still indicates sea level snow for the lower South Island on Monday and ukmet falling into line on this. Dunedin should get snow to very low levels Monday.

Yes ,totally agree with that at this stage, looks a real possibility for snow to low levels due to the position of the low,just wondering if we might get two lows at some point in rotation,might be a long shot but depends on how everything moves.But at this stage I think that Dunedinites should seriously be "battening down the hatches" so to speak

[gllitz]

"Them's inflammatory werds, Karsh!" Absolutely SCANDALOUS! Still a wee ways out to call, but looking more and more promising for low level snow and very cold temps for a lot of areas...I'd say this system will not only affect Dunners, but most of the bottom half of the SI....looks to be hitting them sometime late SUN/early MON...and it looks to be quite a prolonged system, relatively speaking...still time for it ALL to change and fizzle, though!

(I also see that UKMET and NOGAPS are starting to come more in line with GFS...)

EDIT: To quantify the above, see the attached Invercargill and Dundedin AWS meteograms from GFS...wow!

[Lawrence]

Yeah agree there Gllitz. That’s a good deal of snow on them charts even if we half the Numbers.

That low though hasn’t been on track persistently though all the model runs and has been North, South, more east, then west so as you say it's still a bit early to call. And even the last few models have it at different lats and longs, so error margins have been quite large across the board, as we saw early on with GFS ,NOGAPS AND UKMET.
Then that High in the Tasman could once again intensify and send it all down the pan but I’m fairly confident that at this stage the error margin of the High should not change to significantly

The only constant in a lot of the charts has been the Precipitation for the North Island

Been Foggy here this morning and feels quite warm now it has cleared.

[NZstorm]

I think this next winter system will be the biggest snow producer of the winter thus far. Looks active!

[Lawrence]

Just looking closely at the latest models although this system will be mainly for the south and the wind direction usually means that eastern parts of Canterbury and Otago are thus sheltered, there is a possibility that Banks peninsular could get a fair dusting about Tuesday morning. Good amount of turbulence around with a 70% chance of snow. The devil in the detail closer to the time will be where the low or lows sit and the consequential wind direction.

[Janos]

Beautiful day down here today...warm no jerseys and little wind.

[gllitz]

Looks far more promising for Southland/Otago...nothing really for Canty...no moisture and flows are too SWerly...maybe later in the week.

[NZ Thunderstorm Soc]

Beautiful day down here today...warm no jerseys and little wind.

Yes,. would be nice for the nude rugby as shown on TV news this evening

JohnGaul
NZThS

[gllitz]

I see Macquarie Island AWS was on -3C this morning with snow (webcam seemed to show the same)...so the air coming up is definitely cold! Will be interesting to watch how Enderby Is and SW Cape fair through the day as the cold air moves further North and East...

Still don't like our chances in Canty for anything really significant...cold, yes...lots of snow...don't think so...that will be for Southland and Otago, I reckon.

[Nev]

Dunedin Aero was on -2°C this morn and Queenstown on 1°C.

We managed to get down to 9°C here yesterday evening with the NW'er, but oddly enough it warmed up to 12°C, even with the SW change early this morn.

[David]

Looks like the weather is gonna go much colder on Tuesday and stay that way for a while....

[NZstorm]

Coldest most unstable airmass crosses the south early Tuesday with undoubtably snow to sea level in the south.

GFS Thickness chart here for 6am tuesday

EDIT I have just updated from 18Z run.

[gopolks]

Southland and Otago will get a dumping on Tuesday.

I have no idea why they are saying snow showers to 200 metres for Christchurch, I doubt even the top of the port hills will get a light dusting???

[melja]

Southland and Otago will get a dumping on Tuesday.

I have no idea why they are saying snow showers to 200 metres for Christchurch, I doubt even the top of the port hills will get a light dusting???

Um it will be cold enough for snow to sea level its just there may not be enough shower activity

[Lawrence]

Latest models have the low further south so might not be so much precipitation as first thought but still a good amount with possible thunder storms in the mix.
High intensities of snow showers are likely at this point around the Dunstan Range, about Black Gully, Remarkables, around the areas of Waiparu,Queenstown,Arrowtown,Frankton,Dunedin,and the Lindis Pass also the Clutha Area.

Getting really cold around Monday evening.

Canterbury unfortunately misses out again.