SPC MESOSCALE DISCUSSION 0542 FOR...ERN TX/LA/MS
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...

VALID 151708Z - 152000Z

AREAS FROM ERN TX EWD ACROSS LA AND MS ARE BEING MONITORED CLOSELY
FOR POSSIBLE SEVERE WEATHER WATCH EARLY THIS AFTERNOON.

MESOANALYSIS/RADAR WERE SHOWING OUTFLOW BOUNDARY/COLD FRONT
INTERSECTION OVER NWRN LA ATTM WITH STRONG PRESSURE RISES
DEVELOPING BEHIND THE COLD FRONT OVER TXK REGION. AIRMASS ALONG AND
SOUTH OF THE BOUNDARY WAS BECOMING INCREASINGLY UNSTABLE WITH
LATEST OBJECTIVE ANALYSIS DATA SUGGESTING MLCAPE IN EXCESS OF 1500
J/KG FROM EAST TX INTO SRN MS. CONTINUED STRONG HEATING COMBINED
WITH FORCING ALONG THE SWD MOVING BOUNDARIES WILL RESULT IN TSTM
COVERAGE AND INTENSITY INCREASING OVER THE NEXT SEVERAL HOURS.
MARGINAL UNIDIRECTIONAL SHEAR IN THE CLOUD BEARING LAYER SUGGESTS
MULTICELLULAR CONVECTION WITH SOME TENDENCY TO FORM INTO BOWED
SEGMENTS. BACKED LOW LEVEL FLOW AND STRONG BOUNDARY LAYER THERMAL
GRADIENT NEAR THE OUTFLOW BOUNDARY OVER ERN LA/MS MAY ALSO SUPPORT
MESOCYCLONE DEVELOPMENT AND CONSEQUENT LARGE HAIL THREAT IN
STRONGER UPDRAFTS THIS AFTERNOON.

..CARBIN.. 04/15/01