Thunderstorms Eastern SI 5/12/20

[Storm Struck]

Quite possibly one of the more fruitful set ups of the season so far for tomorrow, so I thought its definitely worth a new topic.
High cloud in the morning should clear off as the ridge opens up, this will allow much lighter winds south of Christchurch in the afternoon.
Whether they are NE or lighter Northerly shouldn't be too much of an issue given all the other strong ingredients there.
Upper air is favourable and high Cape values near 900 with - 5c LIs.
The SW looks like a slow mover and might actually converge over the city in the evening, but I'm picking most of the action to be in the usual spots coastal Ashburton down to rangitata is where id have a high risk and 20+mm hail.
Worth a chase I feel.

[Chris W]

Yes looks possibly like a high risk, low risk severe setup for reasons I and others detailed in the general Dec thread already.

MS going moderate from north of Dunedin to south of Chch at the moment, I'd have thought Chch would be moderate as well with possible NE vs SW/S.

https://www.metservice.com/warnings/thu ... rm-outlook

[mikestormchaser]

It looks like our best set up to date. A bit more coastal then it looked in the middle of the week.

The rangitata/ ashburton area would be a good place to set up. So i think ill talk to aaron and jase about heading down that way about lunch time. Id think a Moderate risk from north otago up coastal Canterbury plains with a low risk of severe hail.

[mikestormchaser]

1pm surface wind map showing possible NE sea breeze before the SW.

That might play well in our hands and enhance moisture before the change. Something to keep eye on for tomorrow. As it will put us up to a high risk if there is An onshore breeze

[mikestormchaser]

Jase, aaron, andrew and i will head south today and see what happens. I was reminded that the ashburton santa parade was on today so we will need avoid the township. Last thing we need is to be stuck in a Santa parade while chasing storms

[Orion]

Wind still NW, and unpleasantly gusty over the past half an hour; raindrops splattering down from somewhere aloft.

18.0°C

[NZ Thunderstorm Soc]

I noticed a few lightning hits along the Alps according to the Blitz later this morning.
Looks quite thunderstormic between Grey and Westport at the moment.

[Chris W]

MS have extended the moderate risk to Chch, guessing they feel heating will return after the initial trough passes over shortly, or convergence will develop otherwise. Cloudy right now over Lyttelton, a little windy.

[JP.]

Just started raining lightly in the CBD. Still very warm

[Orion]

Skies now mostly clear above, sunny, 20.7°C.

[snowstormwatcher]

Heavy shower with thunder here now

[trickytiger]

Constant thunder in temuka right now

[JP.]

No rain not much wind in the CBD now and lovely 21c

[Chris W]

Clouds billowing up in the distance west of town, not really sure how far away. I'm in St.Martins at the moment and the sun is out with patches of high cloud around.

[Richard]

Getting quite a heavy shower here at the moment

[Chris W]

Building quickly over there

20201205_155901.jpg

[NZ Thunderstorm Soc]

Just come back from a 'storm chase' observed from around Geraldine. Photos later.
Thunderstorm moving east observed, as reported by TT and SSW in the posts above.
Sadly, wind gone back to a breezy West to NW now.

[Orion]

Hearing thunder

[Chris W]

Home now, can see the top of that Ashburton/Rakaia storm.

20201205_164921.jpg

Not sure if I'm hearing rumbles from it, but it looks wet under there! I am seeing flashes though

[dogmelon]

Ashburton is once again thunderstorm alley.

[Chris W]

Ooh, deep rolling thunder! CG lightning. This is a good show

20201205_170843.jpg

[Orion]

Thunder and rain here. Has become quite dark.

[Orion]

Three seconds from that flash to the thunder...

15.9°C.

[Chris W]

Looks to be building on it's northern flank, could be heading for me. Thunder now quite regular.

[Orion]

Some hail the size of peas in amongst the heavy rain for a couple of minutes.

14.4°C.