NZ Weather Forum

A big spring system in the Tasman this week with lots of thunderstorms.
West coast/Alps is typically the most likely spot for thunderstorms but does look like western North Island will catch some activity as well.

500mb chart for Wednesday.

As expected thunderstorms have developed on the front out to west of the North Island due to the jet stream.
Some of this lightning activity reaching the west of the North Island by late evening today. (Waikato south)

Some awesome formations over the alps this arvo

Occasional lightning to the west here with distant rumbles.

Reports of 3 neighbouring houses struck by lightning in south Manukau Heads, Awhitu Peninsular this morn and fire crews were battling a blaze at a Waikato DOC building in the Pureora Forest Park.

'Storm crosses NZ: DOC building burns after suspected lightning strike' - NZ Herald

Razor wrote:Some awesome formations over the alps this arvo

Same here - western sky was very dark late yesterday afternoon;
same again this morning, looks very black out there and the sun has just disappeared behind a cloud bank.
Fresh NW breeze.

NZstorm wrote:Occasional lightning to the west here with distant rumbles.

In Howick, heard a single rumble of thunder to the west just before 6am.

That was a big thunderstorm over Waitomo this morning.

Rainfall trace for Te Kuiti

Reports of a possible damaging tornado in Awatuna, north of Hokitika, just before 6am this morn…

'Tornado hits South Island's West Coast as lightning hits North' - NZ Herald

Thought this worthy of its own thread given the widespread nature

EDIT extended to 7 Sept based on latest round of TS Outlook

From Metservice:

Valid to: Midnight Thursday 7 Sep 2017

Issued at: 10:56am Wednesday 6 Sep 2017

The unstable westerly flow continues over New Zealand during the second half of Thursday, but the flow does tend southwest over the South Island. Further heavy showers and thunderstorms are expected, especially in western areas.

The is a moderate risk of thunderstorms about the Southern Alps and South Island west coast through Thursday afternoon, but this risk decreases to low during the evening.

Elsewhere, there is a low risk of thunderstorms about the western North Island from Taranaki to Kapiti through the afternoon and evening, and also about western Nelson, Fiordland and coastal Southland. There is also a low risk of a few thunderstorms associated with a southwest wind change about eastern Otago and Canterbury in the afternoon and evening, and about the Kaikoura Coast and southern Wairarapa late in the day.

Any thunderstorms that occur will be accompanied by brief heavy rain, hail and squally wind gusts.

No other thunderstorms or significant convection expected over New Zealand during this period

Hmmm metservice have a low risk out for thunderstorms tomorrow.. Iv had a look at the models and don't quite see a lot there.. yet the LIs show -3 over Christchurch.. I don't quite understand where the models are gathering so much Instability

Levin got some good lightning at about 11:30pm last night woop woop!
video: https://www.facebook.com/mkovesdiphotog ... 352270039/

About to get walloped here. Great lightning and thunder with a juicy line about to pass over according to radar

Lightning and distant thunder observable to W/SW.

Front crossing here now, looking very weak with a burst of rain. Auckland City never looked in the firing line anyway.

That looked a reasonable storm that crossed the Waikato this morning.

Some decent thunderstorms passing over from 2 am to 6 am this morning here in Tawa. The one at 2 am scared the crap out of us.

ME going moderate risk coastal Fringes this afternoon.. I do see convergence around 3pm.. Will keep watch

Auckland looks to have a reasonable chance of a thunderstorm on Saturday. We have missed out on the action so far.

9500 lightning strikes according to the Timaru Herald on Tuesday night and I never saw any of them, but did follow on the Blitz. Most were westward way out to sea rather along the Alps observed from here.

Nice 'tower' going up to the NE of here.

Just observed an interesting raggedy grey cloud towering up to the south-west of here - "snap" I suspect, John!

Some brief, yet impressive (for here) thunderstorms going overhead here at the moment.
So far, had a few very bright flashes and very loud rumbles. Along with some short-lived hail.
Kids excited, cats terrified. Usual story.

I think I'm hearing thunder, some kind of thumping and banging anyway, looks like it on rain-radar...

Orion wrote:Just observed an interesting raggedy grey cloud towering up to the south-west of here - "snap" I suspect, John!

Probably the same cloud but unfortunately it died away but however several interesting cloud forms around the Mt. Peel area did develop later but headed east with lots of virga forms from it, along the direction of that cloud.
Now looking rather dark toward that area as it clears away from here and the sun is shining.
By the way a light NW has popped up here away being calm or a light NE drift all day.

Saw that virga too. Rain here at present and very black to the south-east - and a rainbow