Severe Thunderstorm Warning 29, NWS Rapid City, SD

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY
130 PM MDT SAT MAY 31 2003

19Z SURFACE ANALYSIS HAD WEAK LOW OVER SOUTHEAST MT WITH COLD FRONT
MOVING PAST KIDV. SHORTWAVE OVER ND/SD PUSHING BATCH OF
PRECIPITATION OUT OF SOUTH CENTRAL SD. UNDER COOL AIR ALOFT ISOLATED
-SHRA HAVE DEVELOPED OVER NORTHWEST SD. NEXT SHORTWAVE OF INTEREST
MOVING INTO OR. CONCERN THIS FORECAST MAINLY PRECIPITATION CHANCES.

UPPER PATTERN REMAINS ACTIVE THIS FORECAST CYCLE. WESTERLY FLOW
ALOFT OVER THE WESTERN 1/3RD OF THE US WILL BECOME MORE AMPLIFIED AS
UPPER RIDGE DEVELOPS OVER THE WEST COAST. MEAN UPPER TROUGH OVER THE
EASTERN 2/3RDS DEEPENS OVER THE CENTRAL US AND STAYS LONGER THAN
PREVIOUS RUNS. HENCE...AN UNSETTLED PERIOD EXPECTED THROUGH MID-WEEK.

TONIGHT...EXPECTED ISOLATED PRECIPITATION COVERAGE AS DIURNAL CYCLE
MAKES A FEW -SHRA/TSRA THIS EVENING AND THEN WEAK SHORTWAVE MOVE
FROM ID INTO THE CWA. FOCUS WILL LIKELY ALONG LOW/COOL FRONT AS IT
SAGS SLOWLY SOUTH OVERNIGHT. LOWS NEAR GUIDANCE.

SUNDAY...OR SHORTWAVE RACES INTO WY/MT WITH MODEST FORCING AHEAD OF
IT. SURFACE LOW/COLD FRONT SHIFTS INTO NE...SO INSTABILITY WILL NOT
BE APPRECIABLE...NOR WILL SHEAR. HOWEVER...EXPECT BETTER GENERAL
TSRA COVERAGE TO DEVELOP AHEAD OF UPPER SUPPORT. HIGHS A BLEND OF
POTENTIAL TEMPERATURES AND GUIDANCE.

MONDAY THROUGH THURSDAY...AFTER LULL IN ACTIVITY LATE SUNDAY
NIGHT/MONDAY MORNING...A SERIES OF SHORTWAVES MOVING SOUTH OUT OF
CANADA WILL PROMOTE UNSETTLED WEATHER AND TEMPERATURES SLIGHTLY
BELOW NORMAL. MAY BE TOO HIGH ON TEMPERATURES MID-WEEK...BUT GIVEN
JUNE SUNSHINE IF WE GET ANY SUBSTANTIAL RAYS 70F GOOD BET.

DRY AND SEASONABLE WEATHER RETURNS FRIDAY/SATURDAY.

.UNR...NONE.

HELGESON

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-011200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RAPID CITY SD
643 AM MDT SAT MAY 31 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN SOUTH DAKOTA AND
NORTHEASTERN WYOMING.

.DAY ONE...TODAY AND TONIGHT

THERE IS A CHANCE OF THUNDERSTORMS TODAY AND THIS EVENING ACROSS
NORTHEASTERN WYOMING AND WESTERN SOUTH DAKOTA.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE WILL BE A DAILY CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS
FROM SUNDAY THROUGH WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.