Astronomy, Photography and Weather

General Category => Weather & Atmospherics => Topic started by: martinastro on August 13, 2008, 11:00:43 am



Title: Thunderstorm Outlook - Wed August 13th
Post by: martinastro on August 13, 2008, 11:00:43 am
From Tony Gilbert..

(http://i34.tinypic.com/zvzos9.jpg)

Slight Risk Gen Tstorms 09Z-21Z Northern Sector Eire through to Northern UK and separate region Southern UK

Wrapped occlusion will continue to initiate  convective showers UK and Ireland throughout today (as per map)

Eire & N. UK remain in a poorly sheared environment where any severe event is unlikely ATM.

Convection to the south UK likely to be embedded and to the north of the initial main core. Secondary flux of showers likely to initiate late in the day within the same box. First scattering of showers can be seen across SW UK now (no Sferics ATM) These showers are likely to enter a moderately sheared environment although winds look rather straight lined. Given the increase in speed shear at low levels a tornado or two cannot be ruled out.

Prime risk today small hail and strong gust south UK



Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: martinastro on August 13, 2008, 05:55:54 pm
Just back from a successful hunt. Began at 14.00 and found a high location and watched the storm clouds VERY slowly organize into a big structure. It produced a long duration t-storm over the Sperrins then slowly crept down the mountains and over parts of Maghera. Plenty of thunder, c-gs, I-cs etc. The bolts where not too far away from me so I was taking a big risk. Caught two c-gs on video. The structure was excellent with a highly detailed rim around the intense precip core. The highlight was a big brute of a funnel. A dark twisted form evolved out from the rain free base of the storm on the N side very close to the main rain core. It was a gorgeous object with smooth sides. It was bent and twisted. It did not hang down but was suspended in a horizontal position by strong updraughts. I thought this going to drop into a big tornado!. It was directly N of W over the Sperrins. Fantastic show!. Nearly filled a 2GB card with images and video.


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: Paul on August 13, 2008, 06:48:35 pm
Sounds like you had a fun afternoon Martin! I take it your camera survived the previous ordeal. Can you get the still frames out of the video?

P.


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: martinastro on August 13, 2008, 07:29:36 pm
It was fantastic Paul!. The evening time produced the goods. I'm mightly proud of my camera for holding out for yet another day of storms and rain. I feel like writing to Fujifilm and congratulating them on a very sturdy camera. Got all the images and vid on the computer now. Turns out I got 3 c-g bolts in the clips. One is faint, the other is off centre but a clean hit on the ground however the 3rd is perfect even with small branches. Nothing like the cool one you caught a few years ago but nice enough all the same. I paused the video and the bolts are on a single frame which is good. I don't know how to extract the bolt from the clip but I will have a go on movie maker and see what I can  do. If I'm stuck, would you be able to help me out?. Hopefully I will work it out.

Some series funnel captures from Britain today and a weak tornado.


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: Roman White on August 20, 2008, 04:07:23 pm
(...) I don't know how to extract the bolt from the clip but I will have a go on movie maker and see what I can  do. If I'm stuck, would you be able to help me out?. (...)
That is also a very important question for me.
I have 25 minutes of video during the great T-storm of May.17 in Poltava, and there are many (more than 10) lightnings captured there. When I'll have a free time, I'll try to make some still images or few-seconds videoclips and upload them on my site.


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: martinastro on August 20, 2008, 05:28:54 pm
Hi Roman, use this, it's great!...

http://paul.glagla.free.fr/imagegrab_en.htm


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: Roman White on August 20, 2008, 07:50:16 pm
Many many thanks for the link. Beuatiful freeware. Here is my first image using this programme:
T-storm in Poltava on March, 10 evening (around 17h EET)
(http://i34.tinypic.com/w7ex1.jpg)
I repeat: beautiful software. :)


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: martinastro on August 20, 2008, 08:43:54 pm
Those are great bolts Roman. Looked like a very active storm!!. I'm glad you liked the software..so easy to use isn't it. It will be my top choice from now on.  :)


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: Roman White on October 12, 2008, 01:36:10 pm
The same images I used now to make a gif-animation, hope you enjoy it
(http://i019.radikal.ru/0810/c0/d2a7e97ac935.gif)
I must to make more videos with new t-storms (possibly only next April  :'( ).
But sometimes it's scary to stay outside with a camera when a good t-storm is going on there. I told it before, but I'll repeat: on Aug.29 I had a powerful t-storm (which even produced hail). I was standing in my garden, capturing a video in a hope to get some beutiful lightnings on it. But then the t-storm moved just over my head and severe rain started, I had a luck to run very fast a 50m distance to my house before getting completely wet  :D
So it is better to hunt t-storms while standing under the roof.  ;)


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: brianb on October 12, 2008, 02:11:51 pm
Quote
So it is better to hunt t-storms while standing under the roof.
Safer in a car, I think, at least as long as they still have steel body shells - the metal acts as a Faraday cage & you'll be OK even if the car gets a direct hit. My (convertible) car may not be the best for this purpose as it takes 25-30 secs for the (metal) roof to deploy, if I went storm chasing I'd probably have the roof down for better visibility & would get soaked when the rain starts. Actually in "normal" rain I stay dry so long as I can maintain 50 mph+ as the slipstream deflects the rain over my head, but I'm sure this wouldn't work in heavy thundery rain.


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: martinastro on October 12, 2008, 10:23:54 pm
That's a great animation Roman!. You can really get a sense of movement and speed from that.

Yes, it's very scary being out under lightning trying to catch it on camera. It's good to get some kind of shelter. Best times are catching the storm moving in then retreating before the main precipitation area where the most lightning occurs hits you. But what fun it is!


Title: Re: Thunderstorm Outlook - Wed August 13th
Post by: Roman White on October 13, 2008, 07:30:08 am
Thanks Martin