NZ Weather Forum

Gfs starting to hint at a cold end to the month, wee while out still but nice to finally have something that resembles winter in the outlook

matttbs wrote:Gfs starting to hint at a cold end to the month, wee while out still but nice to finally have something that resembles winter in the outlook

The latest run of EC has 20-30cm of snow down to 200m for next weekend for Canterbury, both GFS and ACCESS also have something big brewing, would have to be the first time this winter that all 3 models have agreed on an event!

Just in time for the start of calving in the south perhaps, luckily shouldn't be too bad compared to if it happened In mid August

Bradley wrote:

matttbs wrote:Gfs starting to hint at a cold end to the month, wee while out still but nice to finally have something that resembles winter in the outlook

The latest run of EC has 20-30cm of snow down to 200m for next weekend for Canterbury, both GFS and ACCESS also have something big brewing, would have to be the first time this winter that all 3 models have agreed on an event!

Yes, we need to keep an eye on this one, it could be a biggie!

Tony this one is a bit confusing in that the moisture levels seem to be quite high for a SW change? It's not like it will be a low sitting off the coast??

Bradley wrote:Tony this one is a bit confusing in that the moisture levels seem to be quite high for a SW change? It's not like it will be a low sitting off the coast??

The low develops east of Wellington, so a warmish moisture feed into the cold air over Canterbury. But thats today's data, doubtless it will swing wildly around over the next week.

ECMWF map for next weekend showing a nice ridge through the South Tasman, need to see the ridge maintained in the modelling otherwise it will be westerly short lived cold event.

The latest run of EC has 20-30cm of snow down to 200m for next weekend for Canterbury, both GFS and ACCESS also have something big brewing, would have to be the first time this winter that all 3 models have agreed on an event![/quote]

Yes, we need to keep an eye on this one, it could be a biggie![/quote]

Just waiting for the Facebook forecasters to pick up on this and post it to the masses......
Northerly picking up in town now

Next weekends cold front that was mentioned yesterday has disappeared from the last 3 runs of EC, I think we can safely say it's not going to happen now

There is still a Winter system showing for next weekend in both GFS & ECMWF, see how it evolves in the models over the next few days.

spwill wrote:There is still a Winter system showing for next weekend in both GFS & ECMWF, see how it evolves in the models over the next few days.

I was referring to the very low level snow event we were talking about, now it is just a dry cold change, nothing special for late July

That's a nice example there spwill of the isobars coming straight up from the ice caps!! However the moisture levels for next Sunday isn't much

mikestormchaser wrote:That's a nice example there spwill of the isobars coming straight up from the ice caps!! However the moisture levels for next Sunday isn't much

See how the models develop, there will be changes every run. Flow direction is always important.

Dean. wrote:The latest run of EC has 20-30cm of snow down to 200m for next weekend for Canterbury, both GFS and ACCESS also have something big brewing, would have to be the first time this winter that all 3 models have agreed on an event!

Yes, we need to keep an eye on this one, it could be a biggie![/quote]

Just waiting for the Facebook forecasters to pick up on this and post it to the masses......
Northerly picking up in town now[/quote]

Didn't take long

Moisture levels picked up a little. Looks like straight southerly on Sunday. At this stage snow to low levels, would possibly be some lightning with some wintry CBs given the upper Temps on the latest run!

Could be cold.

Latest GFS suggests snow down to 300m in the North Island for Sunday. Nice to have a break from the wind today in Auckland.

Appears as though this Southerly coming this weekend is still on track. Showing some really cold air in the models and snow to only a few hundred metres in Canterbury. Should be short lived which farmers with lambs due will be happy about.

At this stage I would say Southland/South Otago look most in the firing for some snow due to the flow direction.

GFS has been consistent with a critical SW scenario for South Island east coast. Dunedin will get the snow on a SSW but miss out on a WSW.
Southland could get lots of snow but Invercargill can miss the action in a SW flow due Stewart Island.

How is central North Island looking? To me it's winding back each run.

I'm considering heading down Sunday morning if it's going to snow in national park village or ohakune.

NZstorm wrote:GFS has been consistent with a critical SW scenario for South Island east coast. Dunedin will get the snow on a SSW but miss out on a WSW.
Southland could get lots of snow but Invercargill can miss the action in a SW flow due Stewart Island.

Looks a Banks Peninsula event for these parts.Will Be fine and cold for us away from the coast....

Looking at the models this looks to be one of the driest cold changes I can remember for inland Canterbury, reminds me of the late May 2013 event where we got 0.5mm in Sheffield for the entire event!

Bradley wrote:Looking at the models this looks to be one of the driest cold changes I can remember for inland Canterbury, reminds me of the late May 2013 event where we got 0.5mm in Sheffield for the entire event!

Colder the air the drier the air really. -38 at 500mb on Sunday! Should be a low topped CB around though that could produce a lightning strike or two

Canterbury in the precipitation shadow with the SW flow however I notice latest run of the EC and GFS have some onshore flow early next week for east coast, perhaps something to watch.