Spectacular lightning storm south of Dunedin 23/9

Compie · Unread post by **Compie** » Sat 23/09/2006 23:32

Hey guys.

I hope to capture some of this on film, there is the coolest lightning storm down here tonight, beautiful evening v wam.

Living in Hokitika beofre I have seen some beauties, but I have just seen looking wsw of dunedin, some of the most stuunnning fork lighning I have ever seen.

Nice

will post pics if I get some

NZ Thunderstorm Soc · Sat 23/09/2006 23:59

....immmm interesting.

Steven Graham's boltex only picking up more further out West Coast storms.
Radio very distantly crackly here.

JohnGaul
NZTS

Compie · Unread post by **Compie** » Sun 24/09/2006 00:24

was all over in minutes, and now of course we have the rain.

Still no wind and still very mild out, but heavy steady rain.

Storm Struck · Unread post by **Storm Struck** » Sun 24/09/2006 00:56

Can see that rain is moving into Canterbury now too Radar at mignight showed it well.
Still few thunderstorms on the west coast can't believe this warm 19C night lets hope it's a warm one later on today.

Cheers
Jason.

JP. · Unread post by **JP.** » Sun 24/09/2006 06:00

I was walking home from a night on the town here (south side of chch) about 5am and low and behold it started raining out of nowhere...

It had been a very warm night nice and mild, when the slight rain started there were huge thunder claps in the distance and massive white basks of light towards the south..

I tried to hurry home to capture it but 40 mins later it was all over..

NZstorm · Unread post by **NZstorm** » Sun 24/09/2006 09:06

Looks likely to have been elevated thunderstorms along the front spilling over from the alps.

The front was quite lightning active overnight, particularly in Westland.

NZ Thunderstorm Soc · Sun 24/09/2006 10:38

I had reports of a few rumbles of thunder from the back of Akaroa about 5am this morning.
Yes indeed a very active system this was. Shame it didn't come to Christchurch

Sadly for us thunderstorms freaks

, it's all over now

JohnGaul
NZTS

mikestormchaser · Unread post by **mikestormchaser** » Sun 24/09/2006 10:42

yeah was a beauty night overnight!
Geez it wasnt as warm as they predicted yesterday infact last night was warmer then all of yesterday it was warm from around 7 pm.
Feels alittle thundery today, quite warm and abit humid aswel. See what happens yeaaaah!

Also what iv heard, better put alil sunscreen on today.Or i might look a tad red tonight

cheers

Storm Struck · Unread post by **Storm Struck** » Sun 24/09/2006 10:51

Just had reports of thunder heard offshore from Caroline Bay in the last 20mins can see some strikes on tracker around that area too.
Was 24.1C back to 19.7C with a cool southerly now.
Pitty those storms didn't cross into Christchurch last night would have been a loud storm as thunder from the west is very loud not to mention the torential rain.
Cheers
Jason.

Paul Mallinson · Unread post by **Paul Mallinson** » Sun 24/09/2006 10:53

What an active front! We had 28,000 strikes on the lightning detection system. Yes, the thunderstorms were elevated. There was very little activity offshore and it was the airmass being lifted over the mountains that was the main trigger. One of the Westland Regional Council raingauges recorded 40mm/hr as the front passed by.

There was potential instability in the layer from about 850hPa up to about 550hPa (shows up as falling wet bulb temperature with height) and this showed up on the forecast guidance. When you have a situation like this, the lift on the front and over the land, cools the temperature profile and the instability is released. In addition, the Total Totals Index reached about 58 and the SWEAT index was forecast to be as high as 460 (as a guide, 300+ for thunderstorms, 400+ for tornadoes). This was part of the reason why we posted a threat chart yesterday giving a high risk of severe thunderstorms which included 'possible damaging tornadoes'. Whether there were any twisters or not we may never be able to confirm, but we may get a sigthing of some damage somewhere.

A very interesting event.

Paul

Weathermad · Unread post by **Weathermad** » Sun 24/09/2006 11:17

Saw that too JP...quite spectacular!

Overnight low was 16 and that came with the arrival of a shower

sw_windbow · Unread post by **sw_windbow** » Sun 24/09/2006 12:22

Yes saw one bright flash in Dunedin last night, and then a long time later came a bang and a muffled rumble. First lightning here in ages.

03Stormchaser · Unread post by **03Stormchaser** » Sun 24/09/2006 14:21

Was in HAmner last night, had rain overnight and this morning. Driving back to Chch saw abit of cu that went up and lowish scud cloud.

Also plenty of burnoffs by farmers, on the way in. All but one under control. Rural fire fighters in action, I think this year it will be a busy one for them!!

NZ Thunderstorm Soc · Sun 24/09/2006 18:20

Thanks for that above there, Paul. Yes, an interesting system all-right and weakoning quickly as it came up against the high.
There was a trace of rain in the gauge here this morning and 0.5mm at West Melton.
Interesting day here in Christchurch. It was Sw or WSW here, then that warm southerly late morning.
Just after noon, the Ne change came through and it clouded over dropping the temperature by 6Â°C
At West Melton there was a cool southerly blowing.

JohnGaul
NZTS

tich · Unread post by **tich** » Sun 24/09/2006 20:03

I noticed a shower towards Chch as I was going over Hilltop about 9.30am this morning. Since then it's been cloudy and cool out here (looked like some mammatus type cloud in morning), but no rain. Should've kept out some of the UV rays in the weakened ozone.

Paul Mallinson · Unread post by **Paul Mallinson** » Sun 24/09/2006 20:07

Yes, another bubble of high pressure moved up the SI east coast in behind the frontal/trough system that gave all the lightning activity - simila to a day or so ago.

Paul

Paul Mallinson · Unread post by **Paul Mallinson** » Sun 24/09/2006 20:10

The next front in the latest series moving onto Fiordland in the afternoon appears to be more stable. In this case the wet bulb temperature generally increases with height and so there is only a low chance of instability release (ie. thunderstorms).

Paul

NZ Thunderstorm Soc · Sun 24/09/2006 21:12

tich wrote:I noticed a shower towards Chch as I was going over Hilltop about 9.30am this morning. Since then it's been cloudy and cool out here (looked like some mammatus type cloud in morning), but no rain. Should've kept out some of the UV rays in the weakened ozone.

If you had of been in Akaroa last night you may of? heard a few rumbles early this morning. No shower here around 9am.

JohnGaul
NZTS

NZ Thunderstorm Soc · Sun 24/09/2006 21:15

Paul Mallinson wrote:Yes, another bubble of high pressure moved up the SI east coast in behind the frontal/trough system that gave all the lightning activity - simila to a day or so ago.

Paul

...this may explain the warm southerly ??

JohnGaul
NZTS

Manukau heads obs · Mon 25/09/2006 13:11

What an active front! We had 28,000 strikes on the lightning detection system

that is a [beep beep] alot!
how does that compare to other active fronts?

ricky · Unread post by **ricky** » Mon 25/09/2006 13:24

I heard that one of the detectors was struck and put out of action... which one was that Paul?

Manukau heads obs · Mon 25/09/2006 13:33

as a comparison, a recent active cold front in the USA , a boltec owner recorded:

650,000 strikes recorded for the 24hr period this past friday. And the majority of that was from noon to midnight. I was getting 150,000 PER HOUR

!!!
but that was a spectaculary active for lightning front, I have been told by people in its path

....i.e more than normal for the midwest....
so that puts our one in good company me thinks

Paul Mallinson · Unread post by **Paul Mallinson** » Mon 25/09/2006 14:29

Ricky, I haven't heard about a lightning sensor being struck, but we did loose two automatic weather stations - Milford and Wanaka. Theory is that they either may have been struck or they suffered power surges or simply the coms was down - not sure.

Brian, 28,000 stikes is quite a few for an event in NZ going by the 4 years or so that we've had the lightning detection network. I would say that we see this sort of activity on a front perhaps a few times a year at a guess. The count for many situations is in the order of hundreds to a few thousand. Years ago I used to work for the Canadian Weather Service and I remember the Alberta Forestry lightning detection network sensing up around 20,000 stikes in an hour or two!!

Paul

NZstorm · Unread post by **NZstorm** » Mon 25/09/2006 19:52

I believe the Haast AWS was struck?

I remember the Alberta Forestry lightning detection network sensing up around 20,000 stikes in an hour or two!!

Alberta would get more than its fair share of severe thunderstorms.

NZstorm · Unread post by **NZstorm** » Tue 26/09/2006 20:03

650,000 strikes recorded for the 24hr period this past friday

Those USA supercells produce a heck of a lot of IC or CC lightning. At a wild guess I would say only about 10% of it is CG's.