NZ Weather Forum

Nev wrote: ↑Mon 18/11/2019 15:15 Great rotational video on TVNZ...

https://www.tvnz.co.nz/one-news/new-zea ... 5246484001

Probably a misocyclone rather than a mesocyclone.

Apparently a lightning strike caused a house fire in Palmerston (South) today.

Amazing footage and photos guys , was there two tornados? Ive recieved photos from parklands area of trees down in a narrow channel. They reported it as a very quick sucession of big gale winds and a train sound, often described with tornados. This was parklands horseshoe lake area.
Not quite as dramatic up here in nelson, but we did have a heavy shower around 2pm with one peel of thunder.

Smaller showers continuing to sneak up through mid-Canty, a much lesser deal at the moment however.

the tornado apparently threw a van 15 metres across a carpark.



https://www.stuff.co.nz/the-press/news/ ... -15-metres

The auto shop that lost its roof is DJ Auto. We do all the import checks on his cars.

Chris W wrote: ↑Mon 18/11/2019 17:15 Smaller showers continuing to sneak up through mid-Canty, a much lesser deal at the moment however.

Becoming weaker as skies slowly clear.
Quite a cool NE to Easterly blowing through here keeping temperatures in the low teens.

NIWA are talking up Wednesday for Christchurch. In the meantime the action is further south in terms of the coastal South Island tomorrow.

Razor wrote: ↑Mon 18/11/2019 12:55 20191118_125309.jpgStarting to look tasty from Hagley Park. Wonder if I'll finish my run dry?

To quote myself, well that escalated quickly! On reflection I'm struggling to remember a more impressive storm. It really had everything. I managed to take shelter at the new library and shot up to the 4th floor to watch it all roll in. Didnt know I was less than 1km from a damaging tornado! The hail was impressive, the gust front, the lightning that flashed right over the Cathedral with simultaneous thunder, reminiscent of some incredible storms I've experienced over the years while tramping in the Southern Alps.

I'm still buzzing! What a memorable day

I tried my darnedest to chase this storm. Followed it from it's inception near Rakaia and up to Chch. Once it went over Chch though it became much to difficult to chase with all the traffic so the best I could do was go around the city (John's Rd, lol John Gaul). I figured keeping on the western side of the storm would lead to better picture opportunities but I was mostly out of luck. Wish the storm did something interesting before it got to Chch but oh well.

I did film the waterspout from near Kainga though so something at least. Although it looked more like a condensation funnel that came down then it happened to go over water sort of thing.

Chris W wrote: ↑Mon 18/11/2019 20:03 NIWA are talking up Wednesday for Christchurch. In the meantime the action is further south in terms of the coastal South Island tomorrow.

Wednesday has always looked more potent in model guidance than today did. Doesn't mean it will end up that way on the day though!

TonyT wrote: ↑Mon 18/11/2019 20:42

Chris W wrote: ↑Mon 18/11/2019 20:03 NIWA are talking up Wednesday for Christchurch. In the meantime the action is further south in terms of the coastal South Island tomorrow.

Wednesday has always looked more potent in model guidance than today did. Doesn't mean it will end up that way on the day though!

Wednesday looks simula to today but over a longer duration into the afternoon so perhaps better timing? Also there looks to be more of an E-NE in afternoon to aswel as another strong jet so it looks good but like you say we hope it holds!

Today's thunderstorm in Christchurch sort of reminded me of days gone past when I lived there.
Usual NE punching in before the actual front come through.
Interesting the vortex forming in the Sydenham area and the waterspouts off shore .
Would of been like old times especially in the 1960s when I got interested in thunderstormic weather as a young lad.

NZ Thunderstorm Soc wrote: ↑Mon 18/11/2019 22:14 Today's thunderstorm in Christchurch sort of reminded me of days gone past when I lived there.
Usual NE punching in before the actual front come through.
Interesting the vortex forming in the Sydenham area and the waterspouts off shore .
Would of been like old times especially in the 1960s when I got interested in thunderstormic weather as a young lad.

It was one of those days john! The citys turn today. Lets hope on wensday we all get something juicy!! More wide spread which i can chase after work.

I like to confirm the tornado as a low end EF1 cause apparently it threw a van 15 metres and lifted a few roofs.

Hmm… I'm no expert, but I actually think the Sydenham vortex looks more like a gustnado than an actual tornado? The van or light truck reportedly 'thrown' 15-20 metres across a parking area in Richmond (presume the handbrake was on) is also at least 2 km north of the Sydenham vortex's apparently more west-east damage trail. There were also reports of some roof damage in New Brighton. So maybe multiple gustnado's with that gust front?

well in the vids taken I could see the vortex rotating clockwise which is how our tornadoes spin. and besides tornadoes dont have to have a funnel to be a tornado. as long as they have a debris cloud which was visible.

there was a waterspout reported at new brighton so maybe that was what caused the roof damage there?

Met Service confirmed it was a Tornado (which would have backed up what they saw from doplar radar etc)

Sounds to me like MS simply based their opinion on videos they'd seen. Gustnadoes look so remarkably similar to tornadoes (minus the condensation funnel connecting it to a parent cloud), that they're often mistaken as such, even by the experts. And MS have been known to change their minds before. Just say'n…

Having watched multiple videos of this thing, I am of the view this was a tornado for sure. Funny thing is watching the storm approach I got a message from a work colleague who mentioned the storm was "tornado warned" in the Metservice severe warning. And within minutes there was such action just a handful of blocks from where I stood.

Correlation does not imply causation.
Happy to be corrected if someone could explain why the Sydenham event wasn't a gustnado? …

Funny we mention a gustnado as earlier i notice dust being kicked up and spun around out near the Christchurch Hospital that was higher than the hospital itself. At that time it definitively look like similar gustnados I have seen. So when I heard about a tornado I didn't think much of it at first. Still between two minds, but that TV1 video looking up at the rotation in the clouds is making me lean toward a weak landspout over gust front.

Nev wrote: ↑Tue 19/11/2019 09:27 Correlation does not imply causation.
Happy to be corrected if someone could explain why the Sydenham event wasn't a gustnado? …

I hope MS put out a detailed blog post about this event

Nev wrote: ↑Tue 19/11/2019 09:27 Correlation does not imply causation.
Happy to be corrected if someone could explain why the Sydenham event wasn't a gustnado? …

I'm happy to run with the Metservice view as per the statements they made in this article. Convince me otherways naysayers

https://www.stuff.co.nz/the-press/news/ ... ch-tornado

Razor wrote: ↑Tue 19/11/2019 09:35

Nev wrote: ↑Tue 19/11/2019 09:27 Correlation does not imply causation.
Happy to be corrected if someone could explain why the Sydenham event wasn't a gustnado? …

I'm happy to run with the Metservice view as per the statements they made in this article. Convince me otherways naysayers

https://www.stuff.co.nz/the-press/news/ ... ch-tornado

"A thunderstorm "spawned" a 15-minute tornado that caused widespread destruction over Christchurch city, but it was a relatively mild weather event"