Unstable Air for the NI around 9-14th Jan

[Tornado Tim]

Yes that storm has nearly been the best I have seen.
I wish it was a bit closer to my location but oh well.
I am sure Matangi will have its day.
The cirrus Anvil on the thunderstorm was great, it was huge!
You could see it go down all the way into Tokoroa and all the way up into the Kaimai Ranges.
Magnifcient!

[TokWW]

I have some early photos of the gestation from Kinleith south of where the cloud formed about 4:45pm and rode home stopping for more photos as it did. Will add to my Flikr site as I have time today - I should have suggested you come down for a drive Tim!! It was great fun - even the family were awed by it...

[Vertigo]

this has been posted around the internet, im not sure who took it.. taken from thames

[Nev]

Here's a few more details about that waterspout last night from Newstalk ZB ...

31 foot launch hoisted by water spout
15/01/2009 0:12:04

A waterspout near Great Barrier Island has picked up a 31 foot launch and thrown it down on its side.

Occupants of vessels in Smokehouse Bay said there was no wind prior to the spout, but then at 10.50pm a "screaming wall of wind" came over the hill and everyone on the bay hunkered down for safety.

Coastguard says the launch was picked up and dumped on its side, leaving the two people aboard with cuts and bruises. The launch was reported to be taking on water but has suffered no serious damage.

The waterspout's arrival at Great Barrier Island followed an awe-inspiring electrical storm in the area that continued for well over an hour.

© Radio Network

Apparently none of the other 30 or so boats in the bay were touched.

EDIT: Smokehouse Bay is at the southern end of Port FitzRoy Harbour, which is in the NW part of Great Barrier Island (just curious because some friends of mine went over there yesterday).

[Razor]

this has been posted around the internet, im not sure who took it.. taken from thames

Please tell me thats a fake someone

[GraemeWi]

I reckon it is a good picture - I've taken pictures of strikes that come out from the cloud a long way before the downwards section, in this image it could be coming out of the cloud directly towards the point of view

[Nev]

Positively charged CG's can travel a few kms ahead of the main storm before before turning vertically towards the ground. They originate from high in the anvil of a CB and, although rare, they are most powerful and dangerous forms of lightning.

[Myself]

Positively charged CG's can travel a few kms ahead of the main storm before before turning vertically towards the ground. They originate from high in the anvil of a CB and, although rare, they are most powerful and dangerous forms of lightning.

In NZ they are very common, more so than other places. Common in Japan also.

[Manukau heads obs]

I did see strikes just before it got dark where the bolt was going out into the blue sky,round the back of the CB, much like that one
(the ground looks very dry though considering how much rain there has been the last month?)

[Philip Duncan]

This is the person who posted that lightning bolt: "This pic was taken just north of the Kopu bridge near Thames at aprox 8pm after seeing a large CB forming. Uploaded by: Philip Brewer Date: 14th Jan, 2009".

I wondered if it was fake too... but leaning towards it being real.

[dogmelon]

Thats one awesome positive lighting strike in that photo, a real "bolt from the blue". Just imagine the BOOM from that baby if you were near it! Well done to the person who captured it, fantastic.

[Nev]

In NZ they are very common, more so than other places. Common in Japan also.

Perhaps I should of said rarer than IC's or negatively charged CG's. Don't recall any on last night's Lightning Detectors'. But yes, it would probably have been a +CG which killed that rider and horse last year.

[CbFan]

Re: Thames pic - The reflection on the car in the foreground suggests genuine to me.

[Tornado Tim]

I just went to coromandel via that route and that landscape is genuine!

[Philip Duncan]

Yeah I think it's legit. I'm going to email the person who sent it in to WeatherWatch to ask how he took it, sound of thunder etc. Would be great to hear more from him!

[Thunder]

Awesome lightning pic! Interesting that it was taken from a car.

And hello Cbfan! long time no see, guess the same goes for me. lol. Still read lots, just haven't posted as much as I noramlly do.

Cheers
Aaron

[Razor]

Cheers for the clarification on the pic team...I'll beleive it now

[Vertigo]

Positively charged CG's

curious, how can you guys tell the strokes polarity? something to do with its striking from the very top? in that case, would negative CG's strike from nearer the base?

[spwill]

Great Lightning shot that. Yes, thats what we were seeing around sunset, lightning striking out of the top and side of the CB into clear air.
I took a similar shot but at night a couple of years back.
http://www.weatherforum.org.nz/phpBB3/d ... &mode=view

[Razor]

Yes- thats the one you got in the Herald was it not? I was living up there then

[Vertigo]

a little gif of the lightning activity.. warning 900kb.
edit: seem to be having hosting trouble.. can anyone not see it?

http://verti.orconhosting.net.nz/lightn ... -01-09.gif

[Storm Struck]

Magnificant shot of the CG, i did wonder when i first looked at it whether it was fake.
Normally CG's come down in the main part of structured CB ie, thunderhead or just below the gust front if seen from a distance.
It seemed strange it came down from the outer Anvil top but then again i have seen bolts in photo's from the States which do a simular thing.
Cheers
Jason.

[Nev]

curious, how can you guys tell the strokes polarity? something to do with its striking from the very top? in that case, would negative CG's strike from nearer the base?

Some of the other guys might be able to full you in on the exact details but, as I understand it, positive CG's produce vastly greater amounts of electricity and last a hella'va lot longer than negative CG's, which can be detected by the type and amount of low frequency electromagnetic waves they produce.

And yes, the more common negatively charged CG's originate from the middle or bottom of a CB and tend to strike the ground near the centre of the storm, whereas positive CG's (bolts from the blue) tend to stretch out horizontally from the anvil before veering to the ground.

[David]

I imagine a storm like that would only form right over Auckland once in a few decades!

A nice day today, temperature has stopped going up for the last hour up because the sun keeps going behind the clouds constantly (and locally as well I think).

[Vertigo]

very locally: greenlane is sunny sunny!