Tornadoes possible today from the Missouri Bootheel to Northwest AL
A classic low instability/high wind shear severe weather case will likely transpire this afternoon from the Missouri Bootheel region into northwest Alabama, including western Tennessee and Kentucky, as a vertically stacked storm system moves through the area. 0-1 km helicity values of 200+ m2/s2 (see 18z RUC analysis at left), with much higher values along a WNW-ESE oriented warm front from the Bootheal across western Tennessee, coupled with extremely cold temperatures aloft (< -20 degrees C at 500 mb) will create ideal conditions for low-topped tornadic supercells from now until 00z or so. Storms will likely explode in an arc just ahead of the upper-level vort max over the next hour or so, and track rapidly northeastward with an enhanced tornado threat as they cross the backed low-level flow along the warm front. A tornado watch has just been issued for this area by the Storm Prediction Center, with a moderate threat of tornadoes (see left). Stay tuned for updates!
http://www.tornadovideos.net/component/content/article/1-latest-news/1134-tornadoes-possible-today-from-the-missouri-bootheel-to-northwest-al
