High Wind in Wyoming, May 13, 2009

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
910 AM MDT WED MAY 13 2009

.DISCUSSION...CURRENT SURFACE ANALYSIS SHOWS LOW PRESSURE OVER
SOUTHEAST MB...MOVING INTO WESTERN ON. MAIN COLD FRONT IS WELL EAST
OF THE AREA...WITH A STRONG SECONDARY COLD FRONT MOVING ACROSS
WESTERN ND AND EASTERN MT AT THIS TIME. SKIES ARE PARTLY CLOUDY IN
GENERAL...WITH SOME INCREASING CLOUDINESS ACROSS THE NORTHWESTERN
CWA. REGIONAL RADARS SHOW SOME SHOWER ACTIVITY ACROSS EASTERN
MT...WITH RAIN AND SNOW SHOWERS ALSO NOTED OVER THE BLACK HILLS.
TEMPS ARE MOSTLY IN THE 40S...WITH SOME 30S ACROSS NORTHEAST WY AND
THE HILLS. NORTHWESTERLY WINDS ARE PICKING UP ACROSS THE AREA.

ONLY MINOR CHANGES MADE TO GOING FORECAST FOR TODAY...PRIMARILY WITH
REGARD TO CLOUDS AND TEMPS. SCATTERED SHOWERS CAN BE EXPECTED ACROSS
NORTHERN PARTS OF THE AREA...AS WELL AS THE HILLS. SNOW SHOWERS WILL
CONTINUE ACROSS PARTS OF THE HILLS AND NORTHEAST WY...WITH SOME
ACCUMULATION POSSIBLE IN SPOTS. HIGHS WILL BE IN THE 40S AND 50S.
THE SECONDARY FRONT WILL MOVE ACROSS NORTHERN PORTIONS OF THE AREA
LATE THIS MORNING AND AFTERNOON. WIND WARNINGS AND ADVISORIES REMAIN
IN EFFECT THROUGH THE AFTERNOON. ADDED FALL RIVER COUNTY TO THE
ADVISORY. STILL LOOKS LIKE THE STRONGEST WINDS WILL BE ACROSS THE
NORTHWEST AND WEST CENTRAL SD PLAINS...BUT WILL HAVE TO WATCH AREAS
A BIT FURTHER SOUTH AND EAST FOR WARNING POTENTIAL AS WELL THIS
AFTERNOON. UPDATED FORECAST HAS BEEN SENT.

PREVIOUS DISCUSSION...CURRENT SURFACE MAP SHOWS LOW PRESSURE OVER
EXTREME NORTHEAST NORTH DAKOTA...WITH COLD FRONT THROUGH EASTERN
DAKOTAS. SECONDARY SURFACE TROF ROTATING THROUGH EASTERN MONTANA.
UPPER LOW OVER EASTERN MONTANA. SKIES ARE CURRENTLY MOSTLY CLEAR
WITH DRY SLOT ACROSS THE AREA.

FOR TODAY...UPPER LOW OVER MONTANA WILL MOVE EASTWARD. STEEP LAPSE
RATES WILL RESULT IN A FEW SHOWERS/THUNDERSTORMS.  AS SECONDARY
SURFACE TROF SWINGS THROUGH THE AREA...WINDS WILL PICK UP IN
INTENSITY. WITH THE TIGHT PRESSURE GRADIENT AND 50-65KT WINDS AROUND
5000FT AGL...WARNING/ADVISORY AREAS LOOK GOOD. NO CHANGES NEEDED TO
CURRENT HEADLINES. HIGH BUILDS IN TONIGHT WITH WINDS DECREASING
RAPIDLY. DRY WITH NEAR AVERAGE TEMPERATURES ON THURSDAY. NEXT UPPER
TROF SWINGS THROUGH THE NORTHERN PLAINS FRIDAY WITH A CHANCE OF
SHOWERS/THUNDERSTORMS.

EXTENDED...UPPER LEVEL RIDGE BUILDS OVER THE WESTERN CONUS THIS
WEEKEND...AND SLOWLY SHIFTS EAST EARLY IN THE UPCOMING WORK WEEK.
THIS WILL BRING DRY CONDITIONS AND A WARMING TREND TO THE REGION.

&&

.AVIATION...A STRONG COLD FRONT WILL MOVE THROUGH THE AREA THIS
MORNING. WINDS WILL INCREASE TO 25 TO 40 KTS WITH THE STRONGEST
WINDS OVER THE SD PLAINS WHERE GUSTS TO AROUND 50 KTS WILL BE
POSSIBLE. OTHERWISE...VFR CONDITIONS ARE EXPECTED.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 6 PM MDT /7 PM CDT/ THIS EVENING FOR
     BENNETT-FALL RIVER-HERMOSA FOOT HILLS-JACKSON-MELLETTE-SHANNON
     -SOUTHERN FOOT HILLS-TODD-TRIPP.

     HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR BUTTE-CUSTER
     CO PLAINS-HAAKON-HARDING-NORTHERN FOOT HILLS-NORTHERN MEADE
     CO PLAINS-PENNINGTON CO PLAINS-PERKINS-RAPID CITY-SOUTHERN
     MEADE CO PLAINS-STURGIS/PIEDMONT FOOT HILLS-ZIEBACH.

WY...HIGH WIND WARNING UNTIL 6 PM MDT THIS EVENING FOR NORTHEASTERN
     CROOK.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RAPID CITY SD
416 AM MDT WED MAY 13 2009

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-141300-
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-
416 AM MDT (516 AM CDT) WED MAY 13 2009

...HIGH WIND WARNING NORTHWESTERN SOUTH DAKOTA AND EXTREME
NORTHEASTERN WYOMING TODAY...
...WIND ADVISORY SOUTHERN SOUTH DAKOTA TODAY...

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

.DAY ONE...TODAY AND TONIGHT

A TIGHT PRESSURE GRADIENT WILL BRING VERY WINDY CONDITIONS TODAY.
NORTHWEST WINDS OF 25 TO 45 MPH WITH GUSTS TO 60 MPH CAN BE
EXPECTED. WINDS WILL QUICKLY DIMINISH THIS EVENING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A CHANCE OF THUNDERSTORMS ON FRIDAY. SEVERE THUNDERSTORMS
ARE NOT EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
1057 AM MDT WED MAY 13 2009

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

0420 PM     HAIL             28 NE NEWELL            45.00N 103.01W
05/12/2009  E0.88 INCH       BUTTE              SD   PUBLIC

0435 PM     HAIL             MUD BUTTE               45.01N 102.88W
05/12/2009  E0.88 INCH       MEADE              SD   PUBLIC

0450 PM     TSTM WND GST     OPAL                    44.89N 102.61W
05/12/2009  M66.00 MPH       MEADE              SD   CO-OP OBSERVER

0524 PM     TSTM WND GST     FAITH                   45.02N 102.03W
05/12/2009  M62.00 MPH       MEADE              SD   ASOS

&&

MERICKSO