Unstable trough

Archive of General Weather
Forum rules
These topics are a read-only archive and may be subject to out-of-date information.

For today's weather discussion head to: New Zealand Weather & Climate
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unstable trough

Unread post by NZstorm »

There are thunderstorms this evening in the front out to the west of Northland/Auckland. Will be interesting to see wether they are still there on tomorrows mornings satellite pic. Front due here in the afternoon.

West Coast/Alps should get some thundery weather too.
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Re: Unstable trough

Unread post by NZ Thunderstorm Soc »

West Coast/Alps should get some thundery weather too.[/quote]

Seems quiet there tonight, no sfericking of any note from I can gather.
No satelite pics since the 0000UTC today from MetService

On a sad note, Canterbury Weather Watchers will miss one of it's long standing members, Mr Pat Brown from Colgate who died last Saturday..
Pat was a keen weather observer and had an amazing collection of weather records going back over the years. For me the amazement of Pat was that he was the only person to observe lightning in the NW Arch cloud canopy. This unusual event would only be observed by someone of Pat's calibre. His funeral is at Colgate on Thursday


JohnGaul
NZTS
User avatar
Michael
Posts: 7210
Joined: Thu 27/03/2003 12:04
Location: Rainy Manurewa, Auckland - "City of Gales"
Has thanked: 0
Been thanked: 1 time
Contact:

Unread post by Michael »

Yeah such "exciting weather" as usual up here :(
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

That's not good news John, Unfortunatly I never got to meat Pat, so....

On a thunderstormy note, I just had to watch my Ts video tapes which alot of the footage is yours John...ahh it's exciting! I also reviewed a tape of which I haven't until today of which I took.....must of been 5 to 6 months ago! It was a thunderstorm at night (11:30pm?) which was firing over the southern Alps, perhaps towards the west coast side more. I stood up on my roof for about 35 - 40 minutes with my video camera trying to get a shot or two of some of the lightning. I can remember that night and how at one point I forgot to hit the record button so I wasn't actually recording anything for about a full 10 minutes of which (murphy's law!) there were some good lightning flashes!, so I ended up only videoing for a full 25 - 30 minutes even though I was up there for longer. So... I looked at the tape today and out of the whole thing I found one flash! It was only sheet lightning (but still looked ok - it takes up about 1/4 of the TV screen) and since it was at night you can see a small bit of a siloute (spelling?) of the southern alps in it and the clouds. I think it looks cool, then again it's about the only lightning I've ever got on a video camera but hey...it's good to me.

Now...how would I get that footage on a computer, then capture that
particular frame, then print it? Does anyone know?

And yes, back to the topic header, hopefully someone will get a bit of thunder today! The metvuw.com radar images for Auckland look like there could be a few Cb's floating about.

Cheers
Aaron Wilkinson
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

Todays front a bit of a fizzer for AK.

I am interested by the observation of lightning in the Canterbury NW arch.
Obviously there must have been some embedded Altocumulus castellanus that developed further into Cumulonimbus.
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

Dean, how could I forget to mention your Ts tape. Man that rain is intense!

Aaron
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

A unstable looking sky over Auckland this morning with a scattering of large Cu. Some crisp looking cumulonimbus into the far SE. Lifted index is around -1.
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

We have had a nice day in Ak with max temp 17.3C, weak westerly breeze. Scattered T/cu producing only isolated showers.

Image

Cumulus congestus in the spring sunshine today.
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

Hi People

Today here in Chch has seen two nice Cb's develop (from my point of view here in Southshore), they for the most part were (and one still is) situated over or beyond the SW outskirts of Chch, perhaps someone could give better detail as to where they were as I viewed them from far away. The 3pm radar shows nothing of the sorts as to Cb development but they were (and one still is) there - note, the second Cb began to develop after or just near the 3pm reading. I took photo's but once again it's on film, the film has nearly finished so I should take them in to get developed soon. My Dad actually just went to Australia and took my little digital camera with him (Dam murphy's law!) so I could've put pic's on the forum tonight but can't. We also have had some good Cu about to with the sun shining from behind as it begins to set in the west. Whether or not the Cb's produced thunder I wouldn't have a clue, if they did I suspect because of those K index readings it would've been very limited.

John, Did you hear or see (video?) anything today. I look foward to your report.

Cheers
Aaron Wilkinson
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

This cb poped up over NW Auckland around 5.30pm this evening producing a localised heavy shower. This photo taken from inner Auckland.

Image
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

0600UTC (6:00pm) 28 August 2003

Surface Data - 93781 36/98 /1908 10083 20021 40132 52018=

Christchurch code = 93781, 36 = Slight or moderate drifting snow (below eye level), 98 = Thunderstorm combined with duststorm or sandstorm.

From this here it shows Chch airport has reported Ts.

Cb's on sat pics look to be in the Tasman/Nelson/Malbourough area aswell as Hawkes bay where one news weather reported a hailstorm just west of here and then finally they look to be all down the west coast of the North Island to New Plymouth. And I saw some in Chch - yeh! A good day!

Awsome picture Steven, what digital camera do you use?

Cheers
Aaron Wilkinson
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Unread post by NZ Thunderstorm Soc »

A bit of an unstable day here in ChCh which led to the absence of the forecasted rain, (mind you with shallow troughs anything can happen) with it being fine but also cloudy at times.
A mixture of clouds from boring flat stratisform types to the unstable cloud forms out along the upper plains. Yes. I did see the forementioned CB form, Aaron but as it was electrically dead, I did not persue it any further. Light SW all day. Last night imagary from the Rakaia radar looked interesting but I heard no reports of anything.
Another "Micheal" day here tomorrow ??

JohnGaul
NZTS
Dean.
Posts: 1710
Joined: Mon 10/03/2003 20:29
Location: Ashburton
Has thanked: 425 times
Been thanked: 525 times

Unread post by Dean. »

Well the few showers have developed this evening as Metservice forecast,heavier precipitation along the Canterbury foothills on the 9.00pm Rakaia radar.
Fencepost are forecasting more widespread rain tommorow morning.
Cheerrs.
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Unread post by NZ Thunderstorm Soc »

Nothing here at the moment and I can see MARS which seems to be the only star/planet in the sky at the moment.
No wind either. Barometer rising too, now 1013.246hPa which is standard barometer pressure. Anything above this point is high pressure and anything below is low presure.

JohnGaul
NZTS
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

Ah good (that they were electrically dead). Well if anything, I was sort of in the right position then to view the Cb's with their anvals towering up..cool stuff! ;)

Where I live in Southshore the Port Hills was actually blocking my view of one of the Cb's so I hoped on my electric scooter and buzzed down the footpath at 18 km/h (really fun!) about 2 1/2 km down the road so I could see it, unfortunately on the way back the battery began to get flat and I had to push it for about 1/2 km....the moral, fully charge your scooter before going to view Cb's!

Cheers
Aaron Wilkinson
http://www.escootersnz.com (site not complete yet)
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Unread post by NZ Thunderstorm Soc »

Chasing CB's on scooters, I don't feel too bad now with my tornado chase last Labour We in Jimmy,my wife's we 1960 'Morry Thou' . Mind you I did stuff a bearing tho'!!!

cheers
JohnGaul
NZTS


Now raining..finally but I think it's starting to clear ?
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

Yes a hint of rain here to John but nothing now (11:36 pm).

When I get my hummer that'll be my chase vehicle, it will put my scooter to shame....This may sound silly but I've had visions of big letters going down the side saying "NZTS" on my future hummer, it would sure be a looker, when the time comes I'll decide what to do. The morry has character, a cool choice for a chase vehicle. ;)

Cheers
Aaron Wilkinson
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

Thing about the Hummer Aaron, it will attract the lightning!
and to answer your camera question Canon Powershot G5.

A few cb's developed again today but no thunder!

Image
well glaciated clouds over Hunua(east AK) about 2pm.

Image
T/cu developing soon to be followed by rain and hail(below)

Image

Image
cb with anvil

Image
Wide angle view (of mud) :)
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

Just add to my previous post...I observed that hail at Milford, on the North Shore, mid pm.

And I'll post this shot too seen its so nice. Waitemata Harbour, late afternoon today, looking north. Spent Cumulonimbus over North Auckland. :)

Image
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

No wonder your pics are very clear, that's a 5.0 megapixel camera! I would love to have something like that, all in good time.

Can you adjust the shutter speeds and does it have bulb? Also, can you adjust the aperture (you know, 1.5 - 22). If it does have bulb (great! good for lightning), but I do understand even though you can get bulb on some digital cameras, there is still a limited amount of time you can hold the shutter open due to it burning out the CCD device.

Those photos are great! Good symmetry in the anvil of the last Cb in your first post of today and the others are cool to, especially the yaughting (spelling?) one. This should be put into a book! “Cb’s of NZ” “Thunderstorms of NZ”, take your pic!

Yes, hopefully my future humvee (3 years away?) will attract lightning, actually I’ve heard one of the safest places to be during a lightning storm is in a car if it’s the only type of shelter at hand. I belong to a thing called the Hummer Mailing List (HML) based in the US and one of the guys on it uses his hummer in season to chase storms whether it be thunder, tornadoes or even cyclones!

Oh well, John and I will get our turn in time with hopefully a Ts or two during this summer.

Cheers
Aaron Wilkinson
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

Aaron,
The Canon G5 does all of that and lots more.

Image

Buildup over E Auckland as seen from Milford. Lots of cloud over me at time hence contrast in light.
NZ Thunderstorm Soc
Posts: 18488
Joined: Wed 12/03/2003 22:08
Location: Raukapuka Geraldine
Has thanked: 1769 times
Been thanked: 1412 times

Unread post by NZ Thunderstorm Soc »

Great photos Steven,
I'm afraid you'll have to become a member of the NZ Thunderstorm Society with shots like that.

JohnGaul
NZTS
User avatar
TonyT
Moderator
Posts: 2878
Joined: Thu 08/05/2003 11:09
Location: Amberley, North Canterbury
Has thanked: 352 times
Been thanked: 1146 times

Re: Unstable trough

Unread post by TonyT »

NZ Thunderstorm Soc wrote:
On a sad note, Canterbury Weather Watchers will miss one of it's long standing members, Mr Pat Brown from Colgate who died last Saturday..
Pat was a keen weather observer and had an amazing collection of weather records going back over the years. For me the amazement of Pat was that he was the only person to observe lightning in the NW Arch cloud canopy. This unusual event would only be observed by someone of Pat's calibre. His funeral is at Colgate on Thursday


JohnGaul
NZTS
I have only just caught up with this news, very sad, Pat was a great contributor, a true weather "nut" who travelled a long way from Coalgate to get to evening Metsoc meetings and always had something positive to contribute. Like many weather enthusiasts he had a great memory for unusual and interesting storm events and always a close eye on the current conditions. He looked to be in his 70s, so the experience collected was considerable. We all lose when people with his experience pass on. RIP.

I hope there will be a short obitury in the Metsoc newsletter.
:(
Thunder
Posts: 2068
Joined: Wed 12/03/2003 19:47
Location: Mt Somers
Has thanked: 19 times
Been thanked: 41 times

Unread post by Thunder »

I second that John!

Wow! this camera seems really good Steven. I'll have to save my penny's!

Cheers
Aaron Wilkinson
User avatar
NZstorm
Posts: 11333
Joined: Mon 10/03/2003 19:38
Location: Grey Lynn, Auckland
Has thanked: 342 times
Been thanked: 361 times

Unread post by NZstorm »

Re Digital Cameras

Aaron, time is on your side. These Cameras are getting better and cheaper with time.

I found this web site useful.

http://www.megapixel.net/
Locked