Hail in Wyoming, June 20, 2008

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
201 PM MDT FRI JUN 20 2008

.DISCUSSION...19Z SURFACE ANALYSIS HAS WEAK HIGH PRESSURE OVER THE
NORTHERN PLAINS WITH SUBTLE LEE TROUGH ACROSS CENTRAL MONTANA INTO
EASTERN WYOMING. TEMPERATURES ARE IN THE 70S AND WINDS ARE
GENERALLY LIGHT. UPPER LEVEL ANALYSIS HAS REGION UNDER WEST TO
NORTHWEST FLOW WITH UPPER LEVEL RIDGE OVER THE GREAT BASIN AREA. A
WEAK UPPER LEVEL SHORTWAVE TROUGH IS CURRENTLY SLIDING ACROSS
SOUTHEAST MONTANA...HELPING TO SPARK A FEW SHOWERS AND
THUNDERSTORMS ACROSS NORTHEAST WYOMING. ELEVATED SURFACE HEATING
HAS ASSISTED IN THE DEVELOPMENT OF THUNDERSTORMS OVER THE BLACK
HILLS.

SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP AND SPREAD
ACROSS THE AREA THIS AFTERNOON. DECENT INSTABILITY AND MARGINAL
SHEAR...COMBINED WITH PASSING SHORTWAVE TROUGH WILL KEEP ACTIVITY
GOING THROUGH THE EVENING HOURS...WITH SEVERE STORMS POSSIBLE.
BEST CHANCES FOR STRONGER STORMS WILL BE ACROSS NORTHEAST
WYOMING...INTO THE BLACK HILLS...AND THROUGH SOUTH CENTRAL SOUTH
DAKOTA. LARGE HAIL AND GUSTY WINDS CAN BE EXPECTED FROM THESE
STORMS. ACTIVITY WILL PUSH EAST AND SOUTH THROUGH THE EVENING.

SATURDAY WILL BE A BIT WARMER...WITH HIGHS INTO THE 80S ACROSS MUCH
OF THE PLAINS...70S IN THE HILLS. ISOLATED AFTERNOON AND EVENING
THUNDERSTORMS ARE POSSIBLE...MAINLY ACROSS THE HILLS AREA. RIDGE
AXIS WILL BUILD OVER THE AREA SUNDAY WITH HIGHS PROBABLY APPROACHING
90 DEGREES IN PARTS OF SOUTHERN SOUTH DAKOTA. RIDGE WILL BEGIN TO
SHIFT EAST OF THE AREA LATE IN THE DAY AS SHORTWAVE ENERGY
APPROACHES FROM THE WEST. STRONG CAP WILL BE IN PLACE ACROSS MUCH
OF THE AREA DURING THE DAY...SO IT WILL BE DIFFICULT TO GET STORMS
GOING...BUT WILL KEEP SLIGHT CHANCES ACROSS THE WESTERN CWA.
BETTER CHANCES CAN BE EXPECTED SUNDAY NIGHT...ESPECIALLY ACROSS
NORTHEAST WYOMING AND NORTHERN SOUTH DAKOTA...AS SHORTWAVE SLIDES
NORTHEAST ACROSS THIS AREA. WEAK COLD FRONT WILL HOLD OFF UNTIL
LATE SUNDAY NIGHT AND MONDAY.

EXTENDED...A FLAT UPR LVL RIDGE WILL PERSIST ACRS THE REGION FOR
MUCH OF NEXT WEEK...WITH SEVERAL SHORTWAVES MOVING THROUGH THIS
RIDGE FOR A CONTINUED CHANCE OF SHOWERS/TSTMS EACH DAY. TEMPS SHOULD
BE A FEW DEGREES ABOVE AVERAGE FOR MUCH OF THE PERIOD.

&&

.AVIATION...SCT TSTMS THIS AFTN/EVE ACRS THE REGION WILL LEAD TO
SOME LOCALIZED MVFR CONDITIONS. OTHERWISE...VFR CONDITIONS WILL
PREVAIL NEXT 24 HOURS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RAPID CITY SD
700 AM MDT FRI JUN 20 2008

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-211300-
BENNETT-BUTTE-CENTRAL BLACK HILLS-CUSTER CO PLAINS-FALL RIVER-HAAKON-
HARDING-HERMOSA FOOT HILLS-JACKSON-MELLETTE-NORTHEASTERN CROOK-
NORTHERN BLACK HILLS-NORTHERN CAMPBELL-NORTHERN FOOT HILLS-
NORTHERN MEADE CO PLAINS-PENNINGTON CO PLAINS-PERKINS-RAPID CITY-
SHANNON-SOUTHERN BLACK HILLS-SOUTHERN CAMPBELL-SOUTHERN FOOT HILLS-
SOUTHERN MEADE CO PLAINS-STURGIS/PIEDMONT FOOT HILLS-TODD-TRIPP-
WESTERN CROOK-WESTON-WYOMING BLACK HILLS-ZIEBACH-
700 AM MDT (800 AM CDT) FRI JUN 20 2008

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

.DAY ONE...TODAY AND TONIGHT

ISOLATED TO SCATTERED THUNDERSTORMS WILL CONTINUE ACROSS THE AREA
THROUGH THE EVENING HOURS AS ADDITIONAL UPPER LEVEL DISTURBANCES
CROSS THE REGION. THERE IS A SLIGHT RISK FOR SEVERE STORMS THIS
AFTERNOON AND EVENING ACROSS MUCH OF NORTHEAST WYOMING...THE BLACK
HILLS...AND SOUTHERN SOUTH DAKOTA. LARGE HAIL WILL BE THE MAIN
THREAT...WITH STRONG WIND GUSTS AND LOCALLY HEAVY RAIN ALSO POSSIBLE
WITH THE STRONGER STORMS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THERE IS A SLIGHT CHANCE FOR AFTERNOON AND EVENING THUNDERSTORMS
ACROSS THE AREA THIS WEEKEND. SEVERE THUNDERSTORMS ARE NOT
EXPECTED AT THIS TIME. DAILY CHANCES FOR THUNDERSTORMS ARE
ALSO EXPECTED DURING THE FIRST HALF OF NEXT WEEK.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED OVER NORTHEASTERN WYOMING AND
WESTERN SOUTH DAKOTA THIS AFTERNOON AND EVENING.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
232 PM MDT FRI JUN 20 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0200 PM     HAIL             3 SE HILL CITY          43.90N 103.53W
06/20/2008  E0.88 INCH       PENNINGTON         SD   PUBLIC

&&

MERICKSO