General December Weather

[NZ Thunderstorm Soc]

Might be an interesting week, next week, for the start of our summer?

[harleyb]

I'm watching closely. Am planning a 5 night tramping trip from December 11 and the brief is "anywhere in the south island" depending on the weather. Hoping for somewhere in the Alps or to the west. Yesterday GFS was hinting at high pressure to the south during that week, good for somewhere like Mt Aspiring NP, then the very next run showed low pressure with the remains of a cyclone mixed in! The following run, a NW flow across the SI with no cyclone remnants in sight. May as well toss a coin this far out, I really have no idea.

[Razor]

I too am looking at the model volatility as I prepare for an 85km mountain adventure race behind Arrowtown and Cardrona next Saurday 9th. Too hard to call right now!

[TonyT]

I too am looking at the model volatility as I prepare for an 85km mountain adventure race behind Arrowtown and Cardrona next Saurday 9th. Too hard to call right now!

Wet and windy. But not dangerous. Take a coat.

[spwill]

I'm in the Hollyford Valley Monday/Tuesday, I have picked a fine weather window by good luck.

[mikestormchaser]

Nice day to start summer in Canterbury. Working in coalgate atm so a nice drive across from rolleston. Wee bit of altocumulus about today but quite a calm day

[NZ Thunderstorm Soc]

Not down here. Clagg all day

[NZ Thunderstorm Soc]

Cloudy and overcast grey day although the cloud did try to break up this afternoon but not really succeeding with clagg returning this afternoon and evening with light easterly breezes today. 14.7C for today.

[spwill]

Monday might be an active day for thunderstorm activity over the central North Island high country, see how this looks on Monday morning.
The risk for isolated thunder Otago/ Canterbury tomorrow Sunday.

[NZ Thunderstorm Soc]

Clearing away overnight to become fine around dawn but cloud increasing from the west with some light rain falling late morning and around noon.
This moving away to the east but with cloudy conditions remaining but then eventually clearing away during the afternoon and becoming fine this evening but with some scattered high cloud.
Mild day eventuating with today's maximum being 19.4C with 1.9mm of rain this morning.
Thunderstorms tomorrow?
I like the way MS put the word "possible" in front of a thunderstorm forecast. Is it just in case a thunderstorm may not eventuate. ?

[spwill]

Risk for isolated thunderstorms over Northland tomorrow, still looking active for the central North Island tomorrow.

[mikestormchaser]

I'm again not liking the profiles for today and can't see the moderate risks out. surface dew points would have to become very warm prior to the front to get things going today.

Definitely thunderstorms for northern/ central North island tomorrow.

[Orion]

Around 26.9°C at the moment, some high clouds aloft.

[Dean.]

High dewpoint for this part of the world

[mikestormchaser]

Higher dew points in Ashburton yes. 13.7C dew point in chch city. That's not to bad, if it got 14 or 15C that's not bad and may induce the instability

[Richard]

Only a 12deg dew point here

[NZ Thunderstorm Soc]

Southerly just gone through with the associated clagg moving across.
Was warm prior to the change, now temperatures are falling away.

[Orion]

Southerly just gone through with the associated clagg moving across.
Was warm prior to the change, now temperatures are falling away.

Ya, I timed a visit out perfectly, the southerly arrived while I was away, could smell the sea at once when I came outdoors.
Clouding up and temp. falling quickly, 23.8°C now. Humidity 41%.
Some bubbly towers trying to form in the north.

[mikestormchaser]

Nope no storms today, southerly through now. Dry and cooling down

[NZ Thunderstorm Soc]

Nope no storms today, southerly through now. Dry and cooling down

Yes, blimmin' hopeless. After a lovely summer's morning, back to the usual clagg and low cloud that have plagued us here so far this summer.
No improvement tomorrow either with cool temperatures and another overcast day with a hint of drizzle.
No good for tomato growing

[Richard]

Once past ChCh the southerly change seem to have slowed back as it didn't arrive here till 4.45.
Never was there any hint of a chance of storms before that wind change.

[Storm Struck]

Was certainly more questionable with today's change in terms of potential storms, as even the upper air was quite warm on -14c compared to -18c with Tuesdays change.
Just little dynamics like that make a huge difference.
Still got quite warm prior to the change with some spots in north Canterbury hitting 30C for the first time this season.

This coming Saturday could potentially see temperatures in the early thirties, with very warm upper air moving in and a ridged NW flow.

[Richard]

That 30deg must have been at lower elevations nearer the coast, only made 25deg here.

[NZ Thunderstorm Soc]

I see, at last, MS have dropped their thunderstorm forecast for Canterbury. It wasn't going to happen anyway?
It's annoying when you keep on hearing on weather forecasts for possible thunderstorms when you know, that it is possibly not going to happen.
MS said "Hail between 10 and 20mm". For this to happen, there must of some big dynamics going on in the upper atmosphere for this to happen which we all know wasn't there?
...anyway , the wind has dropped down with a hint of a light easterly. The clagg has settled in with a bit of drizzle and with it being 11C, I might light the fire again. So far this summer, we have had the fire going each night.

[mikestormchaser]

I see, at last, MS have dropped their thunderstorm forecast for Canterbury. It wasn't going to happen anyway?
It's annoying when you keep on hearing on weather forecasts for possible thunderstorms when you know, that it is possibly not going to happen.
MS said "Hail between 10 and 20mm". For this to happen, there must of some big dynamics going on in the upper atmosphere for this to happen which we all know wasn't there?
...anyway , the wind has dropped down with a hint of a light easterly. The clagg has settled in with a bit of drizzle and with it being 11C, I might light the fire again. So far this summer, we have had the fire going each night.

I agree John, today the atmospheric profiles didn't look at all good which is why I couldn't see the risk. And the shear was light today which wouldn't of helped any forcing so any severe hail risk was off. I feel MetService can do better at times. They have gotten better but days like today is way off. If it was me I would put a little low risk around the McKenzie country region if any where in South island otherwise nothing at all. That's my two cents