Mesoscale Discussion 797

MESOSCALE DISCUSSION 0797
NWS STORM PREDICTION CENTER NORMAN OK
0222 PM CDT TUE MAY 06 2008
AREAS AFFECTED...SERN SD...FAR NERN NEB...NWRN IA
CONCERNING...SEVERE THUNDERSTORM WATCH
265
...
VALID 061922Z - 062115Z
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 265
CONTINUES.
A LINE OF SEVERE THUNDERSTORMS HAS RAPIDLY INCREASED IN INTENSITY
OVER THE LAST HOUR AS IT HAS ENCOUNTERED A MORE UNSTABLE AIR MASS.
SURFACE ANALYSIS SHOWS TEMPERATURES NOW INTO THE UPPER 70S...ALONG
WITH DEWPOINTS INTO THE LOWER 50S. AS A RESULT OF HEATING...LOW
LEVEL LAPSE RATES HAVE BECOME STEEP...ERASING CONVECTIVE INHIBITION.
THE ENVIRONMENT DOWNSTREAM OF THIS CONVECTIVE LINE HAS THUS BECOME
FAVORABLE FOR STRONG EVAPORATIVE COOLING AND DAMAGING WIND
GUSTS...WHICH MAY BECOME FURTHER ENHANCED DUE TO LARGE AMOUNTS OF
HAIL IN THESE STORMS. DAMAGING HAIL WILL REMAIN LIKELY WITH THESE
STORMS AS WELL.
FARTHER W...OUTFLOW HAS STABILIZED MUCH OF THE WRN PORTION OF WW
265...ALTHOUGH AN OUTFLOW BOUNDARY HAS BEEN LAID DOWN. NEW
CONVECTIVE DEVELOPMENT IS LIKELY W AND SW OF THE WATCH...AND THIS
DEVELOPMENT COULD RE-ENTER WW 265 LATER THIS AFTERNOON.
..JEWELL.. 05/06/2008