2012-05-30 MISC: KS/OK/TX

[Tim Vasquez]

Here is the NAM output indicating that short wave trough I mentioned earlier. Click to enlarge. Short wave trough indicated by red line, and 500 mb positive vorticity advection by red shading. Normally I don't see a short wave this clear cut, and it had consistency from 00 to 06 to 12 hr, so I wanted to share it. The caveat is that vorticity diagnostics are sort of an "old school" method, and there are assumptions about thermal advection and vorticity increasing with height in order for the vertical velocity equation to yield upward motion, but generally this method works along with all your other tools. Also it's important to keep in mind that this doesn't actually "trigger" storms but assists with cap removal as it reaches the moist sector.

 

[Ian Miller]

Thanks Tim for the explanation i have been trying to get my head round short wave identification and i
think i have it, it is such a small scale event it takes some tracking on the charts as it approaches.
Thanks again Ian

 

[cdcollura]

Good day all,

First of all (for the MODS) ... You may want to consider the "after / during the event" threads in here into a DISC thread.

I was like the many that targeted the northern target ... With much regret.

Thanks again Tim for pointing out the KEY features of this setup that even SPC did not realize. I will remember this for years to come.

 

[James Hilger]

Torn reported by 2 SN members north of Fairfax,Ok with power flashes

It was me and Derik Masingale. Wasn't on the ground long but was pretty neat seeing the practically the whole tornado being lit up. I don't think it hit any structures.