Hail in South Dakota, August 22, 2012

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
630 PM CDT WED AUG 22 2012

.UPDATE...
LOWERED POPS...ESPECIALLY OVER THE NORTHERN COUNTIES THROUGH THE
NEXT 6 HRS. STORMS ARE STILL EXPECTED TO DEVELOP ALONG THE NOSE OF
THE LLJ THROUGH THIS EVENING BUT THAT WOULD KEEP MOST OF THE
STORMS SOUTH OF THIS CWA. WILL REEVALUATE POST MIDNIGHT POPS AS
NEWER MODEL DATA BECOMES AVAILABLE THIS EVENING TO SEE IF THOSE
NEED TO BE TRIMMED BACK AS WELL.

SEE UPDATED AVIATION DISCUSSION BELOW.

&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
A WEAK AND SLIGHTLY NEGATIVELY TILTED MID LEVEL TROF OVER
ALBERTA/SASKATCHEWAN WILL TRACK EASTWARD ACROSS SOUTHERN CANADA
THROUGH THE NEXT 48 HOURS. THIS TROF ALONG WITH A WEAK COLD
FRONT/DRY LINE SHOULD BRING SCATTERED THUNDERSTORMS TO THE DAKOTAS
AND MINNESOTA TONIGHT THROUGH THURSDAY. A MODEST 30 KNOT LLJ IN
COMBINATION WITH DEW POINTS IN THE LOWER 60S COULD RESULT IN SOME
STORMS BECOMING STRONG WITH GUSTY WINDS AND SMALL HAIL POSSIBLE.

SURFACE TROF REMAINS ACROSS THE EASTERN HALF OF THE CWA ON
THURSDAY. DEW POINTS IN THE UPPER 50S/LOWER 60S WILL PRODUCE
ML-CAPE VALUES AROUND 1500 J/KG. WITH DECENT LOW LEVEL LAPSE
RATES...AFTERNOON CONVECTION WILL BE POSSIBLE IN THE EASTERN CWA.

A STRONGER STORM SYSTEM WILL MOVE ACROSS SOUTHERN CANADA FRIDAY
AFTERNOON THROUGH SATURDAY. THIS STORM SYSTEM WILL BRING BETTER
CHANCES FOR THUNDERSTORMS ACROSS THE REGION FOR FRIDAY NIGHT.
STRONG TO SEVERE STORMS SEEM POSSIBLE...BUT THIS WILL DEPEND ON
THE AMOUNT OF AVAILABLE MOISTURE.

.LONG TERM...SATURDAY THROUGH WEDNESDAY
THE PERIOD STARTS OFF WITH AN UPPER LEVEL SHORTWAVE TROUGH TO THE
NORTHWEST OF THE AREA. THIS WAVE WILL TRACK ACROSS NORTH
DAKOTA...WITH THE MAIN ENERGY REMAINING NORTH OF THE CWA. ZONAL
FLOW THEN SETS UP THROUGH SUNDAY WHEN A RIDGE BEGINS TO BUILD
OVER THE ROCKIES...TURNING THE FLOW NORTHWESTERLY. THE RIDGE THEN
REMAINS DOMINANT UNTIL ANOTHER SHORTWAVE APPROACHES AND TRACKS
ACROSS THE NORTHERN PLAINS ON WEDNESDAY.

A SURFACE COLD FRONT WILL BE SITUATED FROM NORTH TO SOUTH OVER THE
CWA SATURDAY MORNING...AND THERE MAY BE SOME SHOWER OR
THUNDERSTORM ACTIVITY ONGOING WHEN THE EXTENDED PERIOD STARTS.
THE FRONT QUICKLY PUSHES OFF TO THE EAST DURING THE DAY...BRINGING
ANY PRECIPITATION TO AN END BY EVENING. WEAK HIGH PRESSURE THEN
SETS UP OVER THE REGION THROUGH MONDAY. THE MODELS ARE IN GOOD
AGREEMENT THAT ANOTHER FRONTAL BOUNDARY WILL AFFECT THE REGION
LATE IN THE PERIOD...BUT DO NOT AGREE ON TIMING...WITH THE ECMWF
BEING ABOUT 24 HOURS SLOWER THAN THE GFS. THEREFORE...HAVE OPTED
TO JUST LEAVE THE LATTER PART OF THE FORECAST DRY.

NEAR NORMAL TEMPERATURES ARE EXPECTED DURING THE FIRST HALF OF THE
PERIOD...WITH HIGHS MAINLY IN THE 80S. LOOKS LIKE A BIT OF A WARM
UP FOR THE LATTER HALF OF THE PERIOD AS DECENT WAA SETS UP AHEAD
OF THE APPROACHING FRONT. HIGHS IN THE UPPER 80S TO MID 90S WILL
BE COMMON TUESDAY AND WEDNESDAY.

&&

.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

VFR CONDITIONS WILL PREVAIL ACROSS THE AREA THROUGH THIS EVENING. SHOWER
AND THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG A FRONTAL BOUNDARY
MOVING ACROSS THE AREA DURING THE OVERNIGHT HOURS. AT THIS
TIME...HAVE NOT INTRODUCED CIGS OR VSBYS BELOW VFR LEVELS...THOUGH
IT IS POSSIBLE WITH ANY THUNDERSTORMS THAT DEVELOP. THE MOST
LIKELY SITE TO SEE THE REDUCTIONS IN CIGS AND VSBYS WILL BE KATY...MAINLY
BETWEEN 06Z AND 12Z.

&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
&&

UPDATE...WISE
SHORT TERM...SD
LONG TERM...PARKIN
AVIATION...WISE

WEATHER.GOV/ABERDEEN

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
528 AM CDT WED AUG 22 2012

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-231030-
TRAVERSE-BIG STONE-CORSON-CAMPBELL-MCPHERSON-BROWN-MARSHALL-
ROBERTS-WALWORTH-EDMUNDS-DAY-DEWEY-POTTER-FAULK-SPINK-CLARK-
CODINGTON-GRANT-HAMLIN-DEUEL-STANLEY-SULLY-HUGHES-HYDE-HAND-JONES-
LYMAN-BUFFALO-
528 AM CDT WED AUG 22 2012 /428 AM MDT WED AUG 22 2012/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL
MINNESOTA...CENTRAL SOUTH DAKOTA...NORTH CENTRAL SOUTH DAKOTA AND
NORTHEAST SOUTH DAKOTA.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE AREA THIS EVENING
AND THROUGH THE OVERNIGHT HOURS. SMALL HAIL AND GUSTY WINDS ARE
POSSIBLE...BUT THE OVERALL THREAT FOR ORGANIZED SEVERE WEATHER IS
LOW.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THUNDERSTORMS ARE POSSIBLE ACROSS NORTHEAST SOUTH DAKOTA AND WEST
CENTRAL MINNESOTA ON THURSDAY...MAINLY DURING THE MORNING HOURS.
THUNDERSTORMS ARE ALSO IN THE FORECAST FRIDAY NIGHT AND SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

TMT