Severe Thunderstorm Warning 180, NWS Aberdeen, SD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
337 AM CDT WED AUG 25 2004

.SHORT TERM...TODAY THROUGH FRIDAY NITE
STRONG UPPER JET CONTINUES TO PUSH EAST THROUGH PAC NW THIS MORNING.
LEAD SHORT WAVE CURRENTLY IS MOVING THROUGH NORTHERN WYOMING AS
NOTED ON WATER VAPOR IMAGERY. THIS WAVE WILL MOVE THROUGH THE
FORECAST AREA THIS AFTERNOON AND EARLY EVENING WITH SURFACE
LOW/TROUGH DEEPENING OVER THE CENTRAL DAKOTAS. DEW POINTS ARE
EXPECTED TO BE IN THE 60S EAST OF THE SURFACE TROUGH BY THIS
AFTERNOON AS SOUTHERLY WINDS INCREASE. CAPES WILL MOSTLY LIKELY BE
IN THE 1500 TO 2000 J/KG RANGE WITH IMPRESSIVE SHEAR. 0-3 KM
HELICITIES WILL BE 150 TO 200 AND 0-6 KM SHEAR AT 35 TO 40 KTS.
ORGANIZED CONVECTION IS EXPECTED WITH SUPERCELLS POSSIBLE. THE MAIN
TRIGGERS WILL BE THE UPPER LEVEL SHORT WAVE AND THE SURFACE TROUGH.
A WEAK BOUNDARY IS CURRENTLY DRAPED ACROSS THE NORTH THIS
MORNING...BUT IS EXPECTED TO LIFT TO THE NORTH YET THIS MORNING. IF
THIS FRONT IS SLOW TO LIFT NORTHWARD TODAY...IT MAY PROVE TO BE A
FOCUS MECHANISM ALONG THE NORTHERN FRINGES OF THE CWA. COLD FRONT
EVENTUALLY PUSHES THROUGH TONIGHT AND EARLY THURSDAY WITH HIGHS IN
THE UPPER 70S TO LOW 80S FOR THURSDAY. MAIN UPPER LEVEL TROUGH
PUSHES THROUGH DURING THE DAY ON THURSDAY AND HAVE GONE WITH 20 POPS
AREA-WIDE AS STEEP LAPSE RATES WILL ALLOW FOR CAPES IN THE 500-1000
J/KG RANGE. A SECOND COLD FRONT WILL PUSH THROUGH THURSDAY
NIGHT...WITH 850 MB TEMPS DROPPING TO 6-8C BY 12Z FRIDAY. UPPER
TROUGH WILL REMAIN OVER THE ROCKIES INTO FRIDAY...WHILE COOL HIGH
PRESSURE SETTLES INTO THE NORTHERN PLAINS. STRONG ISENTROPIC LIFTING
WILL OCCUR OVER THE NEB/SD BORDER ON FRIDAY...POSSIBLY AFFECTING
THE SOUTHWESTERN PORTION OF THE CWA. CONTINUED WITH 20 AND 30 POPS
SOUTH. FRIDAY LOOKS TO BE EVEN COOLER WITH HIGHS MAINLY IN THE LOWER
70S.

.LONG TERM...SATURDAY THROUGH TUESDAY
THE EARLY PART OF THE EXTENDED PERIOD WILL SEE AN UPPER TROUGH
EXTENDING FROM HUDSON BAY TO THE FOUR CORNERS REGION BEGINNING TO
PUSH TO THE EAST. THIS TROUGH WILL TRACK ACROSS THE PLAINS SOMETIME
DURING THE WEEKEND...WITH THE DGEX BEING A BIT SLOWER THAN THE GFS.
ONCE THE TROUGH MOVES THROUGH...THE UPPER FLOW BECOMES ZONAL ACROSS
MUCH OF THE WESTERN AND CENTRAL PART OF THE COUNTRY. AT THE
SURFACE...HIGH PRESSURE WILL BE OVER MUCH OF PLAINS ON
SATURDAY...WITH A WEAK TROUGH NOSING DOWN OVER THE DAKOTAS. WEAK LOW
PRESSURE THEN REMAINS OVER THE NORTHERN PLAINS...WITH THE HIGH
GETTING PUSHED A BIT TO THE SOUTH. A FRONTAL BOUNDARY DROPS OVER
NORTH DAKOTA ON MONDAY...THEN BECOMES STATIONARY THERE AS THE STRONG
HIGH TO THE SOUTH HOLDS FIRMLY IN PLACE AND THE UPPER FLOW BECOMES
ZONAL. VERY LITTLE MOISTURE INDICATED ON ANY OF THE MODEL TIME
SECTIONS...SO WILL KEEP THE ENTIRE PERIOD DRY.

TEMPERATURES WILL BE THE COOLEST EARLY IN THE PERIOD WITH THE
SURFACE HIGH HAVING MORE OF AN EFFECT. H85 TEMPS START OFF AROUND
+10. ONCE THE HIGH MOVES SOUTH AND SOUTHERLY FLOW SETS UP SOUTH OF
THE STATIONARY FRONT...H85 TEMPS RISE BACK INTO THE UPPER TEENS TO
LOWER 20S. THEREFORE...SHOULD SEE TEMPS BACK ABOVE NORMAL DURING THE
LATTER HALF OF THE PERIOD.

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

KNUTSVIG/PARKIN

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
547 AM CDT WED AUG 25 2004

SDZ003-004-009-015-016-033>036-045-048-051-261020-
BUFFALO-CAMPBELL-CORSON-DEWEY-HUGHES-HYDE-JONES-LYMAN-POTTER-STANLEY-
SULLY-WALWORTH-
547 AM CDT WED AUG 25 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF CENTRAL AND NORTH
CENTRAL SOUTH DAKOTA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA TODAY. HOWEVER...ANY
STORMS THAT DO DEVELOP ARE NOT EXPECTED TO REACH SEVERE LIMITS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

MNZ039-046-SDZ005>008-010-011-017>023-037-261020-
BIG STONE-BROWN-CLARK-CODINGTON-DAY-DEUEL-EDMUNDS-FAULK-GRANT-HAMLIN-
HAND-MARSHALL-MCPHERSON-ROBERTS-SPINK-TRAVERSE-
547 AM CDT WED AUG 25 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PARTS OF CENTRAL...NORTH
CENTRAL AND NORTHEAST SOUTH DAKOTA...AS WELL AS BIG STONE
AND TRAVERSE COUNTIES IN MINNESOTA.

.DAY ONE...TODAY AND TONIGHT

SEVERE THUNDERSTORMS WILL BE POSSIBLE TODAY AND TONIGHT AHEAD OF A
DEVELOPING LOW PRESSURE SYSTEM. THE MAIN THREATS WILL BE LARGE HAIL
AND DAMAGING WINDS...WITH ISOLATED TORNADOS POSSIBLE AS WELL. MOST OF
THE ACTIVITY IS EXPECTED TO OCCUR DURING THE AFTERNOON AND EARLY
EVENING HOURS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ABERDEEN SD
240 PM CDT WED AUG 25 2004

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

0228 PM     HAIL             6 ENE SISSETON          45.70N 96.93W
08/25/2004  0.88 INCH        ROBERTS            SD   PUBLIC

&&

TEAM ABR

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ABERDEEN SD
350 PM CDT WED AUG 25 2004

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

0315 PM     HAIL             8 SE MILBANK            45.14N 96.52W
08/25/2004  0.88 INCH        GRANT              SD   PUBLIC

&&

TEAM ABR