Canty T'storms 01/04/2008?

[mikestormchaser]

thunder and lightning out this way aswel! gale S winds and heavy speradic rian right now to! unusual for a storm to come up around this time of night aye??
Although was expected i did see the storm tracker go abit nutty earlier! anyhow, wahoooooo

[Paul Mallinson]

Yes, its going on rather later than is the usual story in summer because the upper trough is a rather sharp one and there is strong cooling aloft going on.

Paul

[tich]

Heavy rain in central Chch, but eased now. Saw some sheet lightning and possibly heard 1 bit of thunder. (though so much noise from the wind and rain to compete)

[TonyT]

Whats that rustling sound I hear over the top of the distant peels of thunder? Oh yes, it must be Mrs Gaul wrapping up her husband's Jockeys for their journey north to Wellington. Will Mr Mallinson wear them proudly I wonder, or will Mr Rawdon use them to plug the leak in the control room roof?

[sw_windbow]

one more post tonyt and you're in the four figure club.

[Paul Mallinson]

Whats that rustling sound I hear over the top of the distant peels of thunder? Oh yes, it must be Mrs Gaul wrapping up her husband's Jockeys for their journey north to Wellington. Will Mr Mallinson wear them proudly I wonder, or will Mr Rawdon use them to plug the leak in the control room roof?

I like the last idea the best!!!

Paul

[Andrew Massie]

One good photo to show later.. And some good video too, hopefully.. Out Pegasus Bay it was coming straight down CG to hit the water! AWESOME!

Hey JG, photos of these special undies please? Are they special grandad morriss dancing Y fronts?!!!

HEY, look! Talking about posts, I've just done half the posts TonyT has!

[spwill]

I see these storms developed well behind the cooler change. Some moisture coming on shore with the SouthWester + land heat from a warm day reacting with the Trough by the looks.

[Storm Struck]

Now that was unexpected thought it was all over drover, and then hail mary came to town.
I was in the bathroom and heard this silent rumble then baaboomboom, sounded like someone dropping a huge metal balls down some giant stairs .
Then more thunder and lightning followed with breif heavy rain and hail up to pea size.
Got a pic of the hail.
No filming as I wasnt ready for it in time.
What a way to start April .
Cheers
Jason.

April 1st storm 009.JPG

[Andrew Massie]

I was in the bathroom and heard this silent rumble then baaboomboom

Jase, what is a silent rumble?

[Ryan Thomas]

The baaboomboom sounds like the result of being in the bathroom hehe. But there was some pretty impressive sheet lightning earlier but I couldn't be bothered going upstairs to get a better look because it wasn't very frequent

[David]

How lucky for you guys, the last thunder heard here was 18th December last year and the last proper thunderstorm was 1st October. Just like 2006, no thunder for the first three months of the year so far.

[Andrew Massie]

Sorry to hear that David, I have to admit, I was very skeptical that we were going to get any, and got a shock when it did eventuate. All credit to Paul Mallinson! Looks like we're the lucky ones for a change!

Video here:

[Storm Struck]

Started off as a silent rumble almost like just before an earthqauke as you can normally hear it coming, then the kaaboomboom or as John referrs to as dump thunder.
Cheers
Jason.

[mikestormchaser]

well good to see some exciting weather for once, hopefully we start getting some more changes like that more often now, bed time anwyays!!! oh and nice pic Andrew! Go us lol

Also got to love the video aswel man!!! good stuff. but I tkink it was Steves video of the storm that hit Christchurch last october with the band " lightning crashes song" in it is an absolute beauty!

[NZ Thunderstorm Soc]

I was away tonight engaged in activities other than meteorology and was annoyed when I heard the thunder rumbling away and I couldn't do anything about it.

...anyway, Paul. Good forecasting and the underpants will be away in the post shortly


JohnGaul
NZTS

[Paul Mallinson]

I was away tonight engaged in activities other than meteorology and was annoyed when I heard the thunder rumbling away and I couldn't do anything about it.

...anyway, Paul. Good forecasting and the underpants will be away in the post shortly


JohnGaul
NZTS

Thanks, but I want to be frank with you and tell you that while I posted a few comments at times yesterday, I wasn't actually on shift. Congrats go to one of my colleagues who did a good job and who should receive the prize!

Did anyone hear anymore about the tornado Jim mentioned occurring in Westport yesterday afternoon or evening?

One more thing - great picture of the hail there Jasestrm. Its hard to pick the hail stone sizes. Do you have some idea? Would be very interested.

Thanks.

Paul

[NZstorm]

Quite an active polar trough by the looks. The models picked up on it about a week ago but on the day I thought the moisture wouldn't be there.
It is also a bit unsual to get the land based convection post the southerly change. So interesting to see.

[spwill]

land based convection post the southerly change.

I think the air that came in behind the Front was unusually moist ( Evening dewpoints for Chch around 11 - 12C) in relation to the upper air temps and helped generate the later wave of showers and the Thunder for Chch.

[NZ Thunderstorm Soc]

Whats that rustling sound I hear over the top of the distant peels of thunder? Oh yes, it must be Mrs Gaul wrapping up her husband's Jockeys for their journey north to Wellington. Will Mr Mallinson wear them proudly I wonder, or will Mr Rawdon use them to plug the leak in the control room roof?

I laughed until I stopped when I read this posting
Mrs. Gaul said "What a cheek. He should wrap up his own underpants"
.... so I did

JohnGaul
NZTS

[TonyT]

Quite an active polar trough by the looks. The models picked up on it about a week ago but on the day I thought the moisture wouldn't be there.
It is also a bit unsual to get the land based convection post the southerly change. So interesting to see.

But it didnt quite happen that way - the front went through with a period of strong cool westerlies late afternoon, then the southerly change came through a couple of hours later, with the showers and storms. So, I think the convective storms were with the southerly change, its just that the southerly change wasnt with the synoptic scale cold front.

[Paul Mallinson]

Yes, I think Tony has got it about right there.

From memory, as the front went up the west coast there was lots of thunderstorm activity on it and I remember the lightning flashes spreading east of the Alps into eastern Otago and Canterbury. The wind then shifted to west or southwesterly behind that band. (This was the band of activity that spawned the tornado near Westport).
Then the southerly change moved through a while later and the thunderstorms redeveloped on it in the face of cooling surface temperatures, but much more rapidly cooling temperatures aloft driven by the sharp/strong upper trof. As I've suggested before, it is all relative. Even with cool surface temps (given sufficient moisture), if its cold enough aloft, then the convection will occur.

Paul

[spwill]

The interesting point being the Chch storms developed over the cooler surface environment well behind the main change. The first change did produce storms over South Canterbury. I noticed the flow had turned southerly by 7pm at Chch Airport.

[NZstorm]

The interesting point being the Chch storms developed over the cooler surface environment well behind the main change

thats what I meant. I saw a too dry NW ahead of the front in the modelling, also the GFS/UKmet were incorrectly less agressive with the cold upper trough over Canterbury than they had been in previous runs. All adds to the fun of forecasting.

[Andrew Massie]

I noticed quite a bit of mammatus cloud around around 6pm as well.. doesn't that preclude thunderstorm activity (didn't have camera on me)?