SPC MESOSCALE DISCUSSION 0783 FOR CENTRAL AND NRN AR / SRN MO
CONCERNING...SEVERE THUNDERSTORM POTENTIAL...

VALID 181732Z - 182000Z

THUNDERSTORMS DEVELOPMENT IS POSSIBLE ACROSS CENTRAL AND NRN AR /
SRN MO IN THE NEXT COUPLE OF HOURS.  WW MAY BE REQUIRED IN THIS
AREA.

LATEST SATELLITE IMAGERY SHOWS MCV FROM OK MCS MOVING SLOWLY ENEWD
ACROSS FAR NERN OK / SWRN MO.  AREA VWPS / PROFILERS AND 12Z OUN
RAOB INDICATE COMPACT 50 TO 70 KT MID-LEVEL SPEED MAX ASSOCIATED
WITH THIS FEATURE...AND LATEST SRX /FORT SMITH AR/ VWP SHOWS 20 KT
SWLY SURFACE FLOW INCREASING TO 50 KTS FROM THE WEST JUST BELOW 500
MB.  SURFACE PRESSURE FALL CENTER IS INDICATED ACROSS N CENTRAL
AR...WHILE SURFACE WINDS CONTINUE TO RESPOND AND BECOME SOMEWHAT
STRONGER / MORE SELY WITH TIME.

MORNING LIT RAOB SHOWS 7 C/KM MID-LEVEL LAPSE RATE...AND WITH
SURFACE OBS INDICATING LOW 80S TEMPERATURES AND UPPER 60S
DEWPOINTS...SURFACE-BASED CAPE IS NOW IN THE 1500 TO 2000 J/KG
RANGE.  AS DAYTIME HEATING ALLOWS DESTABILIZATION TO CONTINUE...
EXPECT THUNDERSTORMS TO DEVELOP WITH CONTINUED UVV FOCUSED NEAR
SURFACE CONVERGENCE AXIS FROM EAST OF FSM TO EAST OF HRO.  GIVEN
DEEP-LAYER WIND FIELD WHICH HAS BECOME FAVORABLE FOR STORM
ORGANIZATION...EXPECT STORMS TO BECOME SEVERE / PERHAPS
SUPERCELLULAR ACROSS THIS REGION.  MAIN SEVERE THREAT WILL LIKELY
BE DAMAGING WINDS...ALTHOUGH LARGE HAIL AND AN ISOLATED SUPERCELL
TORNADO ARE ALSO POSSIBLE...PARTICULARLY ACROSS NRN AR WHERE LOW-
LEVEL VEERING WILL LIKELY BE MOST PRONOUNCED.   

..GOSS.. 05/18/01