Severe Thunderstorm Warning 72, NWS Rapid City, SD

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
300 PM MDT SUN JUN 24 2001

THUNDERSTORMS WERE POPPING UP OVER ERN WYOMING...THE NEBRASKA
PANHANDLE...AND THE BLACK HILLS THIS AFTERNOON AS SHORTWAVE ENERGY
ENTERING THE AREA PROVIDES THE ADDED BOOST NECESSARY TO BREAK THE
CAP. INVERTED V SOUNDINGS INDICATE THAT GUSTY WINDS WILL BE THE MAIN
THUNDERSTORM THREAT THIS AFTN AND EVENING. STRENGTH OF CAP OVER THE
SC SOUTH DAKOTA ZONES INDICATES TRSA WILL PROBABLY STAY TO THE NORTH
AND WEST THIS EVENING...SO HAVE MENTIONED ISOLATED TSRA EVERYWHERE
BUT OVER SC SD. BEST CHANCE FOR SEVERE WEATHER WILL AGAIN BE OVER
THE FAR NW SD ZONES...AS ANY STORMS THAT DEVELOP IN NRN WY/SRN MT
MAY CLIP THE NW CORNER OF SD AS THEY HEAD NE.

COLD FRONT/SFC TROUGH SAGS SOUTHWARD ACROSS NORTHEASTERN WYOMING AND
WRN SOUTH DAKOTA ON MONDAY. THE FRONT IS EXPECTED TO BE THROUGH ALL
BUT OUR SOUTH CENTRAL SD ZONES BY 21Z. HIGHS TEMPS WILL BE SLIGHTLY
COOLER BEHIND THE FRONT BUT MIXING NEAR THE FRONTAL BOUNDARY WILL
KEEP TEMPS ON THE WARM SIDE. STRONG INSTABILITY BY AFTN WILL BE
FOUND AS MOISTURE POOLS IN THE HOT AIR AHEAD OF THE FRONT...SO
EXPECT TO SEE A FEW THUNDERSTORMS DEVELOP TO THE SOUTH AND EAST OF
THE FRONT MONDAY AFTN AND EVENING. OVERRUNNING WAA WILL BRING A
CHANCE OF SHOWERS AND TSRA TO MUCH OF WRN SD AND NE WYOMING ON
MONDAY NIGHT. SOUTHWESTERLY FLOW ALONG THE WRN EDGE OF THE RIDGE WILL
BRING SHORTWAVE ENERGY OVER NE WYOMING AND FAR WRN SD ON TUESDAY
AFTN/EVE...FOR ANOTHER CHANCE OF TSRA.

IN THE EXTENDED FORECAST...UPPER RIDGE AXIS REBOUNDS OVER THE
CENTRAL PLAINS ON THURSDAY. MRF SWINGS A TROUGH...ALONG WITH SHOWERS
AND THUNDERSTORMS...AND COOLER TEMPERATURES ACROSS THE NORTHERN
PLAINS ON FRIDAY AND SATURDAY. DUE TO THE DRY ATMOS IN PLACE...THE
RAIN COVERAGE AND AMOUNT OF COOLING MAY BE OVERDONE.

.UNR...NONE.

RICHA%RDS