Damaging Wind in South Dakota, September 3, 2014

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1114 PM MDT WED SEP 3 2014

.UPDATE...
ISSUED AT 434 PM MDT WED SEP 3 2014

SMALL UPDATE SENT OUT TO ACCOUNT FOR HIGH BASED CONVECTION
ENTERING NW SD. ALSO ADDED A SLIGHT CHANCE FOR VERY HIGH BASED
CONVECTION LATE THIS EVENING THROUGH EARLY MORNING SE HALF.
POWERFUL MID LEVEL JET STREAK/STEEP MID LEVEL LAPSE RATES/AND
IMPRESSIVE HEIGHT FALLS WILL SUPPORT A CONDITIONALLY UNSTABLE
ATMOSPHERE AS THE UPPER LEVEL TROUGH AND REFLECTED TROUGH ACCESS
SHIFTS SE ACROSS THE FA.

&&

.SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT
ISSUED AT 201 PM MDT WED SEP 3 2014

WATER VAPOR SHOWS INTENSE SHORT WAVE TRACKING EWD ALONG THE
ALTA/MT BORDER...WITH SW FLOW ALOFT THROUGH THE NRN PLAINS. AT THE
SFC...LOW IS DEEPENING OVER SERN MT WITH CDFNT NEARING MILES CITY.
VERY WARM DAY ACROSS THE CWFA WITH TEMPS IN THE 80S TO LOWER 90S.

TONIGHT...CDFNT WILL SWEEP THROUGH THE CWFA...ARRIVING IN RAPID
CITY MID EVENING AND PUSHING THROUGH OUR FAR SCNTRL SD ZONES WELL
BEFORE DAYBREAK. A PERIOD OF VERY GUSTY WINDS GIVEN CORE OF
40-50KT WINDS AROUND 1000FT AGL...5-8MB/3HR PRES RISES...AND
STRONG COLD ADVECTION. AREAS MOST AFFECTED WILL BE NWRN SD AND THE
PLAINS EAST OF THE BLKHLS AND HAVE HOISTED A WIND ADVISORY
BEGINNING 03Z. GIVEN THE VERY DRY AMS IN PLACE...WILL KEEP A DRY
FCST DESPITE SOME ELEVATED INSTABILITY AND WEAK THETA-E ADVECTION.

THURSDAY...WINDY CONDITIONS WILL CONTINUE AS STRONG SHORT WAVE
TRACKS ALONG THE CNDN/ND BORDER AND HIGH PRESSURE BUILDS THROUGH
MT INTO THE WRN DAKOTAS. WINDS SHOULD CONTINUE NEAR ADVISORY
CRITERIA THROUGH MUCH OF THE DAY ACROSS FAR NWRN SO WILL KEEP THE
WIND ADVISORY GOING FOR THAT AREA. DRY CONDITIONS EXPECTED TO
CONTINUE.

&&

.LONG TERM...FRIDAY THROUGH WEDNESDAY
ISSUED AT 201 PM MDT WED SEP 3 2014

STRONG UPPER RIDGING WILL DEVELOP ACROSS THE WRN HALF
OF THE CONUS FOR THE END OF THE WORK WEEK INTO THE WEEKEND. THIS
WILL BRING MOSTLY SUNNY SKIES AND WARMING TEMPS THROUGH SUNDAY.

A BROAD UPPER TROF MOVES INTO THE WESTERN STATES EARLY NEXT WEEK
WITH SOUTHWESTERLY FLOW DEVELOPING OVER THE HIGH PLAINS. COULD SEE
SOME VERY ISOLATED THUNDERSTORM ACTIVITY SOMETIME EARLY NEXT
WEEK...BUT TIMING AND PLACEMENT OF ACTIVITY IS PROBLEMATIC. WILL
KEEP A MAINLY DRY FORECAST GOING IN THE EXTENDED PERIOD UNTIL BETTER
AGREEMENT SHOWS UP IN THE MODEL GUIDANCE. WITH BROAD TROF MOVING
IN...TEMPERATURES WILL GRADUALLY DECREASE FROM MONDAY INTO THE
MIDDLE OF NEXT WEEK.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)
ISSUED AT 1103 PM MDT WED SEP 3 2014

VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD MOST
PLACES. A SHORT PERIOD OF MVFR CIGS CAN BE EXPECTED ACROSS THE
FAR NW SD PLAINS EARLY THIS MORNING AS AN OUTFLOW BOUNDARY SPREADS
SE THERE. A FEW ISOLD TS WILL ALSO BE POSSIBLE OVER SCENTRAL SD
THROUGH EARLY THUR MORNING. OTHERWISE...A STRONG COLD FRONT WILL
CONTINUE TO CROSS THE AREA...BRINGING GUSTY NW WINDS TO THE AREA
OVERNIGHT. GUSTY WINDS WILL RE-DEVELOP ONCE AGAIN LATE THUR
MORNING WITH DIURNAL MIXING...ESP ON THE SD PLAINS AND CONTINUE
FOR MUCH OF THE DAY THURS.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...WIND ADVISORY UNTIL 6 AM MDT THURSDAY FOR SDZ014-025-026-030>032-
     072>074.

     WIND ADVISORY UNTIL 4 PM MDT THURSDAY FOR SDZ001-002-012-013.

WY...NONE.
&&

UPDATE...JC
SHORT TERM...JOHNSON
LONG TERM...15
AVIATION...JC

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE RAPID CITY SD
455 PM MDT WED SEP 3 2014

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-041300-
HARDING-PERKINS-BUTTE-NORTHERN MEADE CO PLAINS-ZIEBACH-
NORTHERN BLACK HILLS-NORTHERN FOOT HILLS-RAPID CITY-
SOUTHERN FOOT HILLS-CENTRAL BLACK HILLS-SOUTHERN BLACK HILLS-
CUSTER CO PLAINS-PENNINGTON CO PLAINS-HAAKON-FALL RIVER-SHANNON-
JACKSON-BENNETT-MELLETTE-TODD-TRIPP-STURGIS/PIEDMONT FOOT HILLS-
SOUTHERN MEADE CO PLAINS-HERMOSA FOOT HILLS-NORTHERN CAMPBELL-
SOUTHERN CAMPBELL-WESTERN CROOK-WYOMING BLACK HILLS-WESTON-
NORTHEASTERN CROOK-
455 PM MDT WED SEP 3 2014 /555 PM CDT WED SEP 3 2014/

...WIND ADVISORY TONIGHT AND THURSDAY FOR NORTHWEST SOUTH
DAKOTA...

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

.DAY ONE...TONIGHT

A STRONG COLD FRONT WILL MOVE INTO NORTHEAST WYOMING AND
NORTHWEST SOUTH DAKOTA EARLY THIS EVENING...AND THROUGH THE
REMAINDER OF WESTERN SOUTH DAKOTA TONIGHT. NORTHWEST WINDS OF 20
TO 30 MPH...WITH GUSTS OVER 50 MPH CAN BE EXPECTED FOR SEVERAL
HOURS AFTER THE COLD FRONT MOVES THROUGH.

THERE IS A SLIGHT CHANCE FOR A THUNDERSTORM THIS EVENING AND EARLY
THURSDAY MORNING...MAINLY OVER THE BLACK HILLS AND SOUTH DAKOTA
PLAINS. SEVERE WEATHER IS NOT EXPECTED.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY.

&&

STAY TUNED TO NOAA WEATHER RADIO FOR FURTHER DETAILS OR UPDATES...
OR CHECK OUR WEB SITE AT WEATHER.GOV/RAPIDCITY

JC

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
1049 PM MDT WED SEP 03 2014

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

1041 PM     NON-TSTM WND GST 5 NE PORCUPINE          43.28N 102.26W
09/03/2014  M60 MPH          SHANNON            SD   MESONET

            PORCUPINE RAWS

&&

POJORLIE