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                                                           May 2nd, 2001
                                                Childress, TX
 
   From mid-level base; to lowering; to forming wall cloud.
   Time: from TC
   Location: 2 mi northeast of Childress, TX

If  I'd gotten down in the Childress, TX area a half hour earlier, I could have added the stage of flat, ambient mid-level rain-free base. Ambient meaning "pre-existing", this is the initial height of the updraft cloud before the storm modifies its environment. This ambient base is the part of the dark cloud seen above my "(C)". This animated GIF, captured from video, shows how a lowered base has already formed in the first frame and how a wall cloud is starting, I stress starting, to build in the second. Many spotters mistake the amount of lowering of the ambient base, or how low the clouds get, as an indication of the intensity of a possible parent mesocylone. As with this storm as an example, of far more importance is the speed of rotation in the parent updraft above any lowerings. Verify if all cloud tags and rain shafts are moving the same direction, indicating that the lowering may well only be because it is in close proximity to a cold hail core. Or is there differential motion, indicating shear, or is it symmetric rotation, indicating a mesocyclone. Let me be clear. Spotters can see rotation, but can't see a mesocyclone. Mesocyclones are only seen by radar, as it is a term to describe the velocity differentials. If you see rotation, call it rotation. If shear, call it shear. Of prime importance are reports of organized, broad-scale rotation seen at cloud base. If the cell is far from the 88D radar, then the circulation you see, might not be seen as a mesocyclone on radar, and organized rotation should always be reported. Spotters should watch for cloud MOVEMENT with more intensity than the height the clouds are off the ground, or even structure for that matter. Circular appearing storms do not produce tornadoes, but the wind circulation in a circular appearing storm can. A timelapse of this well structured, but very weak cell is below!
 
   Timelapse of above forming wall cloud!!!
   Time: 30X : 
   Location: 2 mi northeast of Childress, TX
Large - 711k - (4.0 minutes @ 56kb)
Small - 371k - (2.0 minutes @ 56kb)

 

 
   "The Wall that Was. Despite the Weather!"
   Time: App 8PM
   Location: 5 mi east of Childress, TX

I was delayed a couple minutes from fear of being eaten! Not by this anemic wall, but the farm dog whom I woke up.

 
   "The Scary Wall Cloud"
   Time: from TC
   Location: 5 mi east-northeast of Childress, TX

I say scary in title in jest. Remember when you see the timelapse videos, that they are 30X compression. This storm's speed of motion in timelapse would worry me if I saw it on a cell in realtime! :-)  This storm was not supposed to have a prayer of becoming tornadic, but did have great structure, and if slighly more surface moisture had been present...

I missed the exposure by a stop on this one, plus scanning, turned this into one eerie picture.
 


 
   "The Tornado Chasee"
   Time: from TC
   Location: 5 mi east-northeast of Childress, TX

Actually, "Tornado Chasee" is a registered trade mark of mine.

Ya, right! ;-)  Notice the pencil hanging out of my mouth so I can write down AzRan's.
Exposure on 100 ISO film in the camera behind is 16 seconds at f11.0. Yep. 16. Notice the TRIPOD. Yes, that 3 legged lightning rod. Bogen! Manfrotto!! Would you PLEASE make a tripod out of non-conductive material!!!???  Plastic!?
 


 
   Timelapse of above scary wall cloud!!!
   Time: 30X
   Location: 5 mi east-northeast of Childress, TX
Large - 846k - (4.7 minutes @ 56kb)
Small - 443k - (2.5 minutes @ 56kb)
Remember! This is a 30X timelapse. This means that if you see something on the timelapse that appears that it is moving 3,000 mph!!, then it 'could' be a tornado! :-) 
 

 
   "The Gold and Blue Wall"
   Time: from TC
   Location: 3 mi east of Childress, TX

This wall cloud formed practically where the previous one had. While more intent to get pictures of the sparks, I could tell the motions where fairly weak, and saw only moderate shear at this time. There's a faint spark in the center.