Flash Flooding and Damaging Winds in South Dakota, June 7, 2012

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
340 PM CDT THU JUN 7 2012

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT

PCPN CHANCES ARE THE MAIN ISSUE THROUGH THE SHORT RANGE. FOR TNT
WE HAVE A COUPLE AREAS THAT NEED TO BE WATCHED. FIRST OFF IS A SFC
LOW LOCATED NEAR KMBG WITH A PSEUDO WARM FRONT ACROSS SOUTHERN
NORTH DAKOTA. ML CIN IS FAIRLY LOW ACROSS THIS REGION DUE TO
DIABATIC HEATING AND DECENT SFC DEWPOINTS. A FEW STORMS HAVE
ALREADY POPPED THIS AFTERNOON. HOWEVER SHEAR IS PRETTY PATHETIC
WITH 0-6KM BULK SHEAR LESS THAN 20 KNOTS. THUS THUNDERSTORMS INTO
THE EVENING HOURS COULD BE A LITTLE PULSEY IN THE GENERAL VCNTY OF
THE ND/SD BORDER. LOOKING OUT WEST MOST MODELS DO FORM A LINE OF
STORMS THAT TRACKS EAST ACROSS THE MO VALLEY BEFORE LIKELY
FALLING APART OVER THE JAMES VALLEY. A COUPLE MODELS NAMELY THE
GEM/GFS DO MAINTAIN A WEAK MCS ACROSS THE NORTHEAST CWA LATE. DUE
TO UNCERTAINTY AND ONLY A MODEST LLJ TNT...WILL SIDE WITH MODELS
SUGGESTING STORMS WILL HAVE A ROUGH TIME GETTING INTO THE
EAST...THUS HAVE LOWERED POPS FROM PREVIOUS FORECAST. FOR FRIDAY
THE MODELS SUGGEST A LULL IN THE ACTIVITY UNDER BUILDING HEIGHTS AND
THUS FOR NOW WILL LIMIT PCPN MENTION. HOWEVER FOR FRIDAY NIGHT
THE SFC/H85 WARM FRONT SHOULD BEGIN MARCHING BACK NORTH AND CANT
RULE OUT SOME ELEVATED ACTIVITY AHEAD OF EML ADVECTING OFF THE
WESTERN HIGH PLAINS. SATURDAY STILL LOOKS CAPPED PER GFS SOUNDINGS
AND WARMTH IN THE MID LEVEL THERMAL RIDGE. SATURDAY NIGHT LOOKS
FAIRLY CAPPED TOO...BUT CONVERGENCE IN ADVANCING COLD FRONT MIGHT
BE JUST ENOUGH TO POP A STORM OR TWO SO WILL KEEP SLIGHT CHANCE
IN THE FORECAST. AS FOR TEMPERATURES IT WILL BE QUITE WARM THROUGH
THE FIRST HALF OF THE WEEKEND WITH ABOVE NORMAL TEMPERATURES
EXPECTED. SATURDAY IS EXPECTED TO BE THE WARMEST DAY UNDER VERY
HOT RIDGE ALOFT.

.LONG TERM...SUNDAY THROUGH THURSDAY

MODELS SHOW A COLD FRONT TRACKING ACROSS THE AREA ON SUNDAY WITH
NOT MUCH MOISTURE TO WORK WITH. FRONT IS A RATHER QUICK MOVER AS
WELL SO NOT EXPECTING TOO MUCH IN THE WAY OF PRECIP WITH IT. WILL
MAINTAIN SMALL POPS IN THE FORECAST MAINLY ALONG THE NORTHERN AND
EASTERN CWA. MODELS THEN GO INTO MUCH DISAGREEMENT BEGINNING AS
SOON AS MONDAY. GFS IS MUCH FURTHER SOUTH WITH A POTENT LOW
TRACKING EASTWARD NEAR THE INTERNATIONAL BORDER...AND BRINGS DOWN
MUCH COOLER AIR COMPARED TO THE EC. 12Z EC IS MUCH FARTHER NORTH
WITH THE SURFACE LOW AND THUS KEEPS THE AIR MASS BEHIND THE COLD
FRONT A BIT WARMER. GENERALLY STUCK WITH ALL BLEND TEMPS AT THIS
POINT. SURFACE HIGH THEN SLIDES THROUGH TUESDAY INTO
WEDNESDAY...BUT AGAIN THERE ARE DIFFERENCES OF ABOUT 12 HOURS OF
MOVEMENT OF LARGER SCALE SYNOPTIC FEATURES. INHERITED ALL BLEND
POPS SHOW POPS TOWARDS THE END OF THE PERIOD BUT EC IS RATHER
QUIET ACROSS THE REGION. GFS A BIT MORE ACTIVE BUT THIS REMAINS TO
BE SEEN.

&&

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

VFR CONDITIONS WILL CONTINUE THROUGH THE AFTERNOON AND EVENING
HOURS. BY AROUND 00Z...SCT TSRA EXPECTED ACROSS WESTERN AND
EVENTUALLY INTO CENTRAL SD. THESE COULD AFFECT KMBG AND KPIR.
FARTHER EAST ACROSS KABR AND KATY...TSRA THREAT MUCH MORE
UNCERTAIN AND MODELS SUGGESTING MOST OF THE ACTIVITY WILL DIE OFF
UPON REACHING THE JAMES VALLEY. WILL CONTINUE TO MONITOR. FOR
NOW...HAVE LEFT OUT ANY MENTION OF TS FOR KABR AND KATY.

&&

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

&&

SHORT TERM...TDK
LONG TERM...TMT
AVIATION...TMT

WEATHER.GOV/ABERDEEN

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ABERDEEN SD
336 AM CDT THU JUN 7 2012

MNZ039-046-SDZ003>011-015>023-033>037-045-048-051-080845-
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-
336 AM CDT THU JUN 7 2012 /236 AM MDT THU JUN 7 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 POSSIBLE THROUGHOUT THE DAY AND INTO THE
OVERNIGHT HOURS. A FEW STORMS COULD PRODUCE HAIL AND STRONG
WINDS...THOUGH THE MAIN THREAT WILL BE FOR HEAVY RAIN AS WEAK
WINDS ALOFT SUGGESTS STORMS WILL BE SLOW MOVING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

CONDITIONS BECOME LESS FAVORABLE FOR THUNDERSTORMS FRIDAY WITH
HIGH PRESSURE NOSING INTO THE REGION FROM THE NORTH. SATURDAY
WILL SEE VERY WARM TEMPERATURES ALOFT TO CAP CONVECTION. IF ANY
STORMS DID FORM IN THIS ENVIRONMENT...LARGE HAIL AND STRONG WINDS
WOULD BE THE MAIN THREAT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT.

CONNELLY