Hail and Damaging Winds in South Dakota, June 19, 2012

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
103 AM CDT TUE JUN 19 2012

.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW FOR 06Z TAFS.

UPDATED FOR SEVERE THUNDERSTORM WATCH NUMBER 408 IN EFFECT UNTIL 4
AM CDT.

THE ONLY ADJUSTMENTS TO THE TONIGHT PERIOD OF THE FORECAST WILL BE
TO INSERT SEVERE THUNDERSTORM MENTION ACROSS PRIMARILY THE EASTERN
HALF OF THE CWA. A WARM FRONT ANALYZED ACROSS FAR NORTHERN
NEBRASKA OVER INTO NWRN IOWA/SERN SODAK WILL BE SLOWLY PICKING UP
STEAM...HEADING NORTH ACROSS SOUTH DAKOTA OVER THE NEXT SEVERAL
HOURS. IN ADDITION TO THE FRONTAL BOUNDARY...MOISTURE/INSTABILITY
/KOAX 00Z SOUNDING/ WILL BE ADVECTING UP INTO THIS CWA MAINLY
AFTER 03Z...IN TANDEM WITH A STRENGTHENING LOW LEVEL JET AND
INCREASING UPWARD VERTICAL MOTION ASSOCIATED A MID-LEVEL S/W SEEN
IN WATER VAPOR IMAGERY MOVING INTO WESTERN WYOMING AT THIS TIME.
EFFECTIVE BULK SHEAR IS FORECAST TO BE WELL OVER 50 KNOTS WITH AS
MUCH AS 1500J/KG OF MU-CAPE TO WORK WITH. SUPERCELLS AND/OR OTHER
ORGANIZED CONVECTIVE SYSTEMS CERTAINLY HAVE THE POTENTIAL TO
DEVELOP ACROSS PORTIONS OF CENTRAL INTO NORTHEASTERN SOUTH DAKOTA
WITHIN THE NEXT 3 TO 6 HOURS. UPDATED ZONES/GRIDS WILL BE OUT
SHORTLY.

&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT

PCPN CHANCES REMAIN THE FORECAST CHALLENGE THROUGH THE SHORT
RANGE. FOR TNT DECENT WARM FRONT WILL SET UP ACROSS SOUTHERN SOUTH
DAKOTA AND THEN ADVECT NORTH OVERNIGHT AS NEXT PIECE OF MID LEVEL ENERGY
BEGINS EJECTING INTO THE NORTHERN PLAINS. WAA SHOULD LEAD TO
ELEVATED STORMS...ESPECIALLY LATE TNT. SOME OF THE STORMS WILL BE
ABLE TO TAP ENOUGH MOISTURE/INSTABILITY AND THEREFORE BE ABLE TO
PRODUCE HAIL WITHIN STEEPENING LAPSE RATE ENVIRONMENT. A FEW
STORMS ARE EXPECTED TO LINGER ACROSS THE NORTHEAST CWA IN THE
MORNING...AND THEN DEPENDING UPON HOW FAR EAST THE FRONT GETS ON
TUESDAY...WE COULD SEE SOME REDEVELOPMENT OF ACTIVITY IN THE FAR
EAST ON TUESDAY AFTERNOON.

FOR TUESDAY NIGHT AND WEDNESDAY THERE ARE MAJOR DIFFERENCES IN
THE MODELS. THE EURO MODELS CONTINUE TO CRANK OUT A FAIR AMOUNT OF
POST FRONTAL RAIN IN AREA OF DECENT UVM ACROSS EASTERN SOUTH
DAKOTA. ALL OF THE MODELS TO SOME EXTENT SHOW THE LIFT/UVM...BUT
THE NCEP MODELS ARE MUCH LESS AGGRESSIVE WITH THE POST FRONTAL
COVERAGE AND AMOUNTS. FOR NOW WILL TAKE A MIDDLE OF THE ROAD
APPROACH AND WAIT FOR FUTURE MODELS RUNS TO REFINE.

AS FOR TEMPERATURES THEY SHOULD FAVOR NEAR NORMAL...BUT THEY MAY
BE TOO WARM ACROSS THE EAST ON WEDNESDAY IF THE EURO MODELS ARE
CORRECT.  STAY TUNED.

.LONG TERM...THURSDAY THROUGH MONDAY
THE LONG TERM MODELS AND GFS ENSEMBLES AGREE WELL WITH THE LONG
WAVE PATTERN EVOLUTION ALONG WITH AN IMPORTANT SHORT WAVE TROUGH
MOVING THROUGH FRIDAY AND SATURDAY. WEAK SURFACE HIGH PRESSURE
RIDGING ACROSS THE REGION ON THURSDAY MORNING WILL BE BUILDING
EASTWARD THROUGH FRIDAY AFTERNOON. THURSDAY WILL BE DRY AND MOSTLY
SUNNY WITH LIGHT WINDS AND HIGHS IN THE UPPER 70S TO THE LOWER
80S. FOR FRIDAY AND FRIDAY NIGHT...SURFACE LOW PRESSURE WILL BE
MOVING IN FROM THE WEST WITH THE PRESSURE GRADIENT TIGHTENING UP
QUITE A BIT INTO FRIDAY EVENING. THUS...WARM AND MOIST SOUTH WINDS
WILL BE INCREASING ON FRIDAY AS A WARM FRONT SURGES NORTHWARD IN
ADVANCE OF THE SURFACE LOW. THE LLJ WILL ALSO BE IMPINGING ON THE
REGION MAINLY EAST. HIGHS FOR FRIDAY WILL BE MOSTLY IN THE 80S
WITH LOWER 90S SOUTH IN THE WARM FRONTAL REGION. ALL MODELS SHOW
THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS FRIDAY AFTERNOON AND
NIGHT AND CONTINUING INTO SATURDAY MORNING MAINLY NORTH AND EAST
IN THE REGION. THUS...STILL HAVE IN GOOD CHANCES OF RAINFALL FOR
THIS TIME PERIOD. SATURDAY AND SUNDAY WILL SEE DRY AND SLIGHTLY
COOLER CONDITIONS AS CANADIAN HIGH PRESSURE NOSES INTO THE
REGION. HIGHS WILL BE MAINLY IN THE UPPER 70S TO THE MID 80S FOR
BOTH DAYS. MONDAY WILL BE THE BIG WARM UP OUT WEST AS THE UPPER
HEIGHTS RISE AND SOUTH WINDS PICK UP AGAIN BRINGING IN HOT AIR
MAINLY OUT WEST. COULD SEE QUITE A FEW 90S ALONG AND WEST OF THE
MISSOURI RIVER BY LATE MONDAY AFTERNOON WITH MOSTLY SUNNY SKIES.

&&

.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

SHOWERS AND THUNDERSTORMS WILL CONTINUE NORTH OF A WARM FRONT
THROUGH THE OVERNIGHT HOURS. THE STRONGEST STORMS ARE EXPECTED TO
OCCUR BETWEEN 6Z AND 9Z...WITH LINGERING STORMS THROUGH 12Z. WITH
ANY STORMS...MVFR...TO BRIEF IFR CONDITIONS ARE POSSIBLE. A COLD
FRONT WILL MOVE ACROSS THE REGION TUESDAY...SWITCHING WINDS TO THE
NORTHWEST. THE FRONT WILL ALSO BE THE FOCUS FOR ADDITIONAL
THUNDERSTORM DEVELOPMENT ACROSS EASTERN SOUTH DAKOTA AND WEST
CENTRAL MINNESOTA TUESDAY AFTERNOON AND EVENING.

&&

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

UPDATE...DORN
SHORT TERM...TDK
LONG TERM...MOHR
AVIATION...SERR

WEATHER.GOV/ABERDEEN

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
1039 AM CDT MON JUN 18 2012

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-191545-
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-
1039 AM CDT MON JUN 18 2012 /939 AM MDT MON JUN 18 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

THUNDERSTORMS ARE EXPECTED TONIGHT ACROSS THE AREA. WHILE
WIDESPREAD SEVERE WEATHER IS NOT ANTICIPATED...A FEW STORMS COULD
BECOME SEVERE WITH HAIL BEING THE MAIN THREAT.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

THUNDERSTORMS WILL BE POSSIBLE THROUGH WEDNESDAY. WHILE WIDESPREAD
SEVERE WEATHER IS NOT ANTICIPATED...SOME THUNDERSTORMS TUESDAY
AFTERNOON COULD REACH SEVERE LIMITS IN EASTERN SOUTH DAKOTA AND
WESTERN MINNESOTA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

TDK