000
FXUS63 KABR 052121
AFDABR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ABERDEEN SD
321 PM CST THU DEC 5 2013

.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT

MOSTLY SUNNY SKIES ACROSS THE CWA THIS AFTERNOON WITH STREAMERS
COMING OF THE WARMER WATERS OF LAKE OAHE. WILL SEE MOSTLY CLEAR
SKIES INTO THE EVENING AS WELL SO TEMPERATURES WILL BEGIN TO
TUMBLE AFTER SUNSET AS WINDS SLOWLY DIMINISH. MAIN STORY DURING
THE SHORT TERM PERIOD WILL BE THE VERY COLD TEMPERATURES AND WIND
CHILLS. LOWS TONIGHT WILL FALL INTO THE TEENS BELOW ZERO WITH WIND
CHILL VALUES IN THE 20S TO AROUND 30 BELOW ZERO. BY FRIDAY
MORNING...SOME AREAS ARE EVEN AS COLD AS 30 TO 35 BELOW ZERO WIND
CHILL. WILL LEAVE THE WIND CHILL ADVISORY IN PLACE BUT EASTERN
AREAS OF THE CWA MAY HAVE TO BE EXTENDED THROUGH SATURDAY MORNING.
DID NOT EXTEND AT THIS POINT BECAUSE THERE WILL BE A CUTOFF
SOMEWHERE OVER THE MIDDLE OF THE CWA WHERE WINDS DROP OFF TO LESS
THAN 5 MPH AT SOME POINT FRIDAY NIGHT. DIDNT WANT TO GET TOO CUTE
AT THIS POINT AND TRY TO DETERMINE EXACTLY WHERE THAT WILL
BE...THEN HAVE LATER SHIFTS ADJUST A ROW OR TWO OF COUNTIES AND
MAKE THINGS CONFUSING. LATER SHIFTS CAN EXTEND THE EAST ONCE A
BETTER DETERMINATION IS MADE AS TO EXACTLY WHERE WINDS DROP OFF
ENOUGH SO THAT THEY DO NOT HAVE AN EFFECT ON WIND CHILL. SATURDAY
MORNING WILL BE THE COLDEST PART OF THE PERIOD WITH SOME LOCATIONS
IN THE 20S BELOW ZERO FOR ACTUAL AIR TEMPERATURE. MODELS ARE
SUGGESTING THERE MAY BE SOME CLOUD COVER TO CONTEND WITH SO AN
INTERESTING LOW TEMP FORECAST TO SAY THE LEAST.


.LONG TERM...SUNDAY THROUGH THURSDAY

THERE IS A REASONABLE AGREEMENT AMONG THE LONG RANGE MODELS WHICH
LEADS TO A FAIRLY HIGH FORECASTER CONFIDENCE. THERE IS SOME
DIFFERENCES BETWEEN THE GFS/ECMWF BY THURSDAY AND BEYOND HOWEVER.

THE PERIOD BEGINS WITH A BROAD UPPER LEVEL TROUGH OF LOW PRESSURE
LIFTING NORTHEASTWARD ACROSS THE REGION. AS OF NOW...THIS SYSTEM
LACKS SIGNIFICANT LOW LEVEL MOISTURE AND UPPER LEVEL LIFT...WHICH
SHOULD LEAD TO A HIGH POP/LOW QPF EVENT. SNOWFALL AMOUNTS OF A
HALF INCH TO PERHAPS TWO INCHES COULD BE POSSIBLE.

A CLIPPER SYSTEM PASSING THROUGH THE REGION MONDAY NIGHT/TUESDAY
MORNING WILL BRING THE NEXT CHANCE FOR LIGHT SNOWFALL. THIS
CLIPPER SYSTEM WILL LIKELY PRODUCE GUSTY NORTHWEST WINDS WITH
AREAS OF BLOWING SNOW POSSIBLE. THE ECMWF IS SHOWING 925 MB WINDS
OF 35 TO 40 KNOTS...MAINLY ON THE LEE SIDE OF THE PRAIRIE COTEAU.
IF THESE WINDS ACTUALLY OCCUR...A HEADLINE MIGHT BE NEEDED IN THE
FUTURE.

BEYOND THE MONDAY NIGHT CLIPPER SYSTEM...THE ECMWF IS SHOWING
INCREASING MID LEVEL HEIGHTS WITH WARMER SURFACE TEMPERATURES
MOVING INTO THE REGION BY THURSDAY. THE GFS IS MORE PESSIMISTIC
AND KEEPS NORTHWEST FLOW ALOFT WITH COLDER TEMPERATURES. WILL
MAINTAIN COOLER TEMPERATURES FOR NOW...AS MOST OF THE NORTHERN
PLAINS HAS SNOW COVER.


&&

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

VFR CONDITIONS EXPECTED FOR ALL SITES. THE CAVEAT IS SOME MVFR
RELATED LAKE EFFECT CLOUDS NEAR KPIR AND KATY WHICH WILL PERSIST
OFF AND ON THROUGH THE DAY. WINDS WILL REMAIN OUT OF THE
WEST/NORTHWEST BUT WILL GRADUALLY WEAKEN THROUGHOUT THE DAY.


&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WIND CHILL ADVISORY UNTIL 6 PM CST /5 PM MST/ FRIDAY FOR BROWN-
     BUFFALO-CAMPBELL-CLARK-CODINGTON-CORSON-DAY-DEUEL-DEWEY-
     EDMUNDS-FAULK-GRANT-HAMLIN-HAND-HUGHES-HYDE-JONES-LYMAN-
     MARSHALL-MCPHERSON-POTTER-ROBERTS-SPINK-STANLEY-SULLY-
     WALWORTH.

MN...WIND CHILL ADVISORY UNTIL 6 PM CST FRIDAY FOR BIG STONE-TRAVERSE.

&&

$$
SHORT TERM...TMT
LONG TERM...SD
AVIATION...SD

WEATHER.GOV/ABERDEEN