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Hail Shaft?

Joined
Sep 2, 2008
Messages
86
Location
Newcastle, UK (the weather sucks here!)
There was a hail shower, so I ran to get the camera, couldn't find it, but by the time I did it stopped. Luckily I still got this photo:
23l1vfn.jpg


I assumed it was a hail shaft, and someone at the Torro website agreed aswell, but on the FTT chat room, they said it was too dark for a hail shaft, and it may be a pendant cloud. What do you think it is?
 
Interesting, you know whats really crazy about that picture is if you look at and squint you might think your looking at a tornado. Normally I see a hail shaft and invision it being white surrounded by grey/dark clouds. Must not have saw that in the chat with you...
 
Hard to tell from the photo, but looks like precipitation downdraft. Given the darkness of it, I'd say it isn't a pure hail or snow downdraft ... but since you saw hail, then there as probably hail. Way to get out and get a shot, though! Good instinct!
 
Small microburst perhaps? Note towards the bottom of the shaft, the outward appearance as if it's "spreading out" from surface impact.
 
I have a couple of similar pictures from a chase last year (on the Windsor, CO day) that I assumed were a microburst, but haven't heard of a hail shaft. How would one distinguish the two? These pictures occurred basically out of a clear cloud base in the vicinity of some cycling weather (clouds popping up and collapsing). It didn't seem to hit the ground and flare out like a microburst, but rather "evaporated" fairly quickly. As you can see from some of the other shots in the gallery, there was a fair bit of hail that day as well.

Anyway, hope these shots don't confuse the original question. I would be interested to know more about what causes hail shafts and how to identify them too.

Gallery: http://www.aircrafter.org/boggs/stormchasing/2008-05-22/

IMG_2127_pic.JPG


Notice the vortices on the side of the shaft as it descends!
 
Hail shafts in the right lighting can appear brilliant white in color. They are most often seen in the hook or just north of the updraft base in supercells. Study supercell schematics. Here's one we saw this year:

08052221.jpg


Looking north. The RFD notch is lighting up a heavy precip core behind it that no doubt has a lot of hail in it.
http://www.skip.cc/chase/080522/08052221.jpg
 
Adam, your pic looks like soild precipitation fallout, likely snow. Thats how it looks to me. As for Sams photo I assumed it was taken in the recent cold outbreak over the UK, late October, so I thought hail or snow.
 
The dark appearance is likely due to a rain shaft. Hailstones, particularly large ones, are ineffective at restricting visibility. Sure hailstones are larger than raindrops, but hailstones are much more widely separated. In general, the smaller the precipitation particles, the more effective they will be at restricting visibility (and appearing dark).

Large hail stones (up to baseball size) were falling near the tornado in the image below, but note the intense sunshine that filtered through anyway.

tornado.gif
May 31, 1990 Waka, Texas (Howard Bluestein, University of Oklahoma)
 
This was from a "chase" March 31, 2008 - under tornado watches/warnings at the time. Hail to nickle size fell, when given the all clear, grabbed my camera and caught this. Made prettier by the dark background of cloud and sun coming out. First time I ever captured a hail shaft.
 

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