Tornadoes and Hail in South Dakota, June 1, 2012

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
326 PM CDT FRI JUN 1 2012

.SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT
FORECAST CHALLENGES INCLUDE THUNDERSTORM STRENGTH AND COVERAGE
THIS EVENING AND AGAIN LATE SATURDAY NIGHT THROUGH SUNDAY
AFTERNOON.

CURRENTLY...AN AREA OF LOW PRESSURE IS WORKING SOUTHEAST INTO
SODAK AND DRAGGING A WARM FRONT/SURFACE THROUGH THE REGION ALONG
WITH IT. EARLIER SHOWERS ARE WORKING OVER THE FAR SOUTHEASTERN
ZONES WHILE DAYTIME-HEATING AIDED SHOWERS AND THUNDERSTORMS ARE
DEVELOPING IN AND MOVING SEWD WITH THE SURFACE BOUNDARY. SHEAR IS
DECENT /0-6KM SHEAR OF 35 TO 40 KNOTS/...HOWEVER LIMITED
SURFACE-BASED MOISTURE IS HOLDING CAPE VALUES BACK GENERALLY
AROUND 500-1000J/KG WITH LITTLE OR NO CONV INHIBITION OUT THERE.
TEMPERATURES EAST OF THE BOUNDARY ARE GENERALLY IN THE 60S WHILE
READINGS BEHIND THE BOUNDARY ARE WARMING INTO THE 70S.

LATE THIS AFTERNOON THROUGH THIS EVENING...WEAK TO MODERATE
CONVECTION MOVING ALONG/WITHIN THE SURFACE TROF WILL CONTINUE TO
PUSH SOUTHEAST AND EVENTUALLY OUT OF THE CWA. NOT EXPECTING MUCH
MORE THAN SOME SMALL HAIL AND 35 TO 45 MPH WIND GUSTS OUT OF
CONVECTION THROUGH THIS EVENING.

THE REMAINDER OF TONIGHT AND SATURDAY...AS WELL AS THE FIRST HALF
OF SATURDAY NIGHT LOOKS DRY WHILE A WEAK RIDGE STARTS TO BUILD
ALOFT OVER THE NORTHERN PLAINS. THERE IS A NOTEWORTHY LOW LEVEL
JET SETTING UP ACROSS THE CWA SATURDAY NIGHT...ALONG WITH SOME
MOISTURE RETURN. THERE MAY BE SOME LATE NIGHT CONVECTION
DEVELOPING OVER THE CWA ON THE NOSE OF THE LOW LEVEL JET AND
BEST MOISTURE ADVECTION...MAINLY AFTER 06Z SUNDAY. OR...A
DIFFERENT SOLUTION IS CONVECTION DEVELOPS OVER THE NORTHERN HIGH
PLAINS SATURDAY EVENING AND EVENTUALLY ATTACHES ITSELF TO THE LOW
LEVEL JET/MOISTURE ADVECTION AND RIDES THE UPPER LEVEL RIDGE INTO
THE EARLY MORNING HOURS ON SUNDAY. EITHER WAY...HAVE INCLUDED SOME
LOW POPS FOR LATE SATURDAY NIGHT/EARLY SUNDAY FOR THIS.

MODELS ALSO DEPICT INCREASING INSTABILITY...COUPLED WITH DECENT
0-6KM SHEAR SUNDAY AFTERNOON ACROSS THE PRAIRIE COTEAU EASTWARD AS
A SURFACE COLD FRONT WORKS ACROSS THE CWA. STILL INCORPORATING
SOME LOW POPS FOR THE EASTERN THIRD OF THE CWA ON SUNDAY FOR
POTENTIAL CONVECTIVE DEVELOPMENT THERE.

TEMPERATURES WILL BE NEAR TO ABOVE NORMAL THROUGH THE WEEKEND.

.LONG TERM...MONDAY THROUGH FRIDAY
BY AND LARGE...THE EXTENDED WILL SEE A PROLONGED PERIOD OF UPPER
LEVEL RIDGING IN PLACE OVER THE NORTHERN PLAINS. THIS WILL
EFFECTIVELY STEER MOST IMPULSES OF LOW PRESSURE ENERGY EITHER WELL
SOUTH AND EAST /UNDERCUTTING THE RIDGE/ OF THIS AREA...OR NORTH
AND WEST OF THIS AREA FOCUSED MORE-SO ACROSS THE NORTHERN HIGH
PLAINS OF MONTANA AND WYOMING WITH STEERING FLOW BECOMING ALMOST
MERIDIONAL AT TIMES. GENERALLY SPEAKING...THE LOW LEVEL THERMAL
ADVECTION PATTERN THROUGHOUT THE EXTENDED SHOULD BE MOSTLY
NEUTRAL AIR TO WARM AIR ADVECTION...ALTHOUGH SYSTEMS RIDING DOWN
THE BACKSIDE IF THIS NOTABLY STRONG UPPER RIDGE INTO THE GREAT
LAKES REGION MAY TRY TO FORCE A COUPLE OF BACK-DOOR COLD FRONTAL
PASSAGES INTO THE NERN FORECAST ZONES. FOR THE MOST PART...ANY
POPS/WX MENTION IN THE EXTENDED IS RELEGATED TO THE FAR WESTERN
PORTION OF ZONES...UNTIL VERY LATE IN THE PERIOD...WHEN THE
GUIDANCE FROM SOME OF THE LONGER RANGE MODELS SUGGESTS UPPER LEVEL
ENERGY WILL TRY TO WORK EAST ACROSS THE NORTHERN PLAINS KNOCKING
THE UPPER RIDGE DOWN. TEMPERATURES SHOULD BE HOLDING GENERALLY
NEAR TO ABOVE NORMAL FOR MOST OF THE EXTENDED PERIOD.

&&

.AVIATION...
18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS

SCATTERED SHOWERS AND THUNDERSTORMS WILL BE MOVING SOUTHEAST
ACROSS THE REGION THROUGH THE AFTERNOON WITH A SHORT WAVE TROUGH
AND SURFACE COOL FRONT MOVING THROUGH. EXPECT THESE TO AFFECT ALL
TAF LOCATIONS IN THE VICINITY OR AT THE STATION. WILL AMEND IF
NECESSARY. OTHERWISE...IT SHOULD BE VFR THROUGH TONIGHT AND
SATURDAY MORNING. IT WILL CLEAR THIS EVENING WITH LIGHT WINDS
OVERNIGHT AND SATURDAY MORNING.

&&

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

SHORT TERM...DORN
LONG TERM...DORN
AVIATION...MOHR

WEATHER.GOV/ABERDEEN

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
422 AM CDT FRI JUN 1 2012

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-020930-
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-
422 AM CDT FRI JUN 1 2012 /322 AM MDT FRI JUN 1 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 SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WILL MOVE
ACROSS THE AREA TODAY. ANY STORMS THAT DEVELOP ARE EXPECTED TO BE
WEAK IN NATURE WITH NO SEVERE STORMS ANTICIPATED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A FEW THUNDERSTORMS ARE POSSIBLE SATURDAY NIGHT INTO SUNDAY
MORNING WITH THE SEVERE STORM THREAT LOW AT THIS TIME. FROM LATE
THIS WEEKEND THROUGH NEXT WEEK...ON AND OFF CHANCES FOR
THUNDERSTORMS ARE IN THE FORECAST...MAINLY FOR WESTERN AND CENTRAL
SOUTH DAKOTA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

TMT

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
440 PM CDT FRI JUN 1 2012

SDZ006-010-018-012215-
BROWN-EDMUNDS-SPINK-
440 PM CDT FRI JUN 1 2012

...A SIGNIFICANT WEATHER ADVISORY HAS BEEN ISSUED FOR EASTERN
EDMUNDS...NORTHWESTERN SPINK AND SOUTHWESTERN BROWN COUNTIES UNTIL
515 PM CDT...

AT 437 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CRAVEN CORNER...OR 7 MILES EAST OF
IPSWICH...MOVING SOUTHEAST AT 25 MPH.

A FEW LOCATIONS IN THE ADVISORY INCLUDE MINA.

SMALL HAIL...AND WINDS AROUND 40 TO 50 MPH ARE EXPECTED WITH THIS
STORM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS. IF YOU CAN HEAR
THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING.

&&

TDK