Shawna Davies
EF1
First of all, I hope I'm posting this correctly. If not, then Mods please move it or do whatever you need to do for this post to be in compliance with the rules of the board. (I did read the special rules sections, but am still not sure.)
Following is some information about yesterday's cold-core event in OK that Jon Davies asked me to post for the people who chased yesterday, or for anyone that might have an interest.
Shawna
Here's a few graphics from yesterday's setup in w-c OK...
surface map 22z:
http://members.cox.net/jondavies6/032006sfc2243anno.gif
satellite 2215z:
http://members.cox.net/jondavies6/032006sa2215anno.gif
NIDS radar image 2215z w/suggested boundaries:
http://members.cox.net/jondavies6/032006rd2215tlx_anno.gif
SPC meso graphics (0-3 km lapse rate, 0-3 km cape, sbcape):
http://members.cox.net/jondavies6/032006spcllr21.gif
http://members.cox.net/jondavies6/032006spccp321.gif
http://members.cox.net/jondavies6/032006spcsbcpe22.gif
Looks like the Dewey county cell was at the intersection of a N-S wind shift and the occluded section of the Pacific front/dryline just east of the surface low. Nice focus with lots of cold air aloft at this location, the 500 mb low over sw KS. Note the surface thermal axis and the steep low-level lapse rates "pointing" into the general area where the tornadic storm occurred. This seems to emphasize that sunshine and sfc heating is needed for these type of events. Thankfully, they are usually weak, but fun to chase and study.
I looked at a RUC20 profile for Watonga at 22z. Even with a sfc Td in the mid 40s F, there was 600-700 J/kg CAPE for low-level ML parcels (-26 C at 500 mb, -7 C at 700 mb), with the fattest CAPE centered at only 600 mb, and the EL near 400 mb. MLLCL around 1000-1200 m, MLLFC not far above that.
Neat to see snow being reported at GAG (22z) not that far away from the tornado location (!).
Following is some information about yesterday's cold-core event in OK that Jon Davies asked me to post for the people who chased yesterday, or for anyone that might have an interest.
Shawna
Here's a few graphics from yesterday's setup in w-c OK...
surface map 22z:
http://members.cox.net/jondavies6/032006sfc2243anno.gif
satellite 2215z:
http://members.cox.net/jondavies6/032006sa2215anno.gif
NIDS radar image 2215z w/suggested boundaries:
http://members.cox.net/jondavies6/032006rd2215tlx_anno.gif
SPC meso graphics (0-3 km lapse rate, 0-3 km cape, sbcape):
http://members.cox.net/jondavies6/032006spcllr21.gif
http://members.cox.net/jondavies6/032006spccp321.gif
http://members.cox.net/jondavies6/032006spcsbcpe22.gif
Looks like the Dewey county cell was at the intersection of a N-S wind shift and the occluded section of the Pacific front/dryline just east of the surface low. Nice focus with lots of cold air aloft at this location, the 500 mb low over sw KS. Note the surface thermal axis and the steep low-level lapse rates "pointing" into the general area where the tornadic storm occurred. This seems to emphasize that sunshine and sfc heating is needed for these type of events. Thankfully, they are usually weak, but fun to chase and study.
I looked at a RUC20 profile for Watonga at 22z. Even with a sfc Td in the mid 40s F, there was 600-700 J/kg CAPE for low-level ML parcels (-26 C at 500 mb, -7 C at 700 mb), with the fattest CAPE centered at only 600 mb, and the EL near 400 mb. MLLCL around 1000-1200 m, MLLFC not far above that.
Neat to see snow being reported at GAG (22z) not that far away from the tornado location (!).