000
FXUS63 KABR 030548 AAA
AFDABR

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ABERDEEN SD
1148 PM CST MON DEC 2 2013

.UPDATE...
06Z AVIATION DISCUSSION UPDATED BELOW.

ECHOES STARTING TO INCREASE ON UNR`S RADAR THIS EVENING AS LIFT
BEGINS TO INCREASE FROM AN ADVANCING SHORT WAVE TROUGH ALONG WITH
INCREASING WAA. ARCTIC BOUNDARY WAS ALSO MOVING SOUTHWARD THIS
EVENING. MOST AREAS HAVE FALLEN TO 32 OR BELOW THIS EVENING.
THUS...CHANGED ALL WEATHER TO SNOW FOR TONIGHT WITH THE BEST
CHANCES AFTER MIDNIGHT AS LIFT SPREADS IN FROM THE WEST. ADJUSTED
WEATHER AND POPS. ALSO...ADDED IN SOME AREAS OF FOG THROUGH
MIDNIGHT OR SO FAR EAST IN THE CWA.


&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
MAIN FORECAST CHALLENGE CONTINUES TO BE PRECIPITATION AMOUNTS AND
IMPACTS EXPECTED FROM THE STORM CURRENTLY APPROACHING THE AREA. AS
THE SURFACE LOW DROPS FROM EASTERN WYOMING TO NEBRASKA
TONIGHT...SNOW LOOKS TO SPREAD ACROSS THE CWA...AND WILL THEN
CONTINUE THROUGH THE DAY TUESDAY AND TUESDAY NIGHT BEFORE
BEGINNING TO TAPER OFF DURING THE DAY WEDNESDAY. THE MODELS
CONTINUE TO BE IN POOR AGREEMENT WITH FORECAST SNOW AMOUNTS. IN
GENERAL...HAVE STUCK WITH A MIDDLE OF THE ROAD BLEND BETWEEN THE
MODELS...WHICH STILL RESULTS IN ANYWHERE FROM 2 TO 8 INCHES OF
ACCUMULATION ACROSS THE CWA...WITH THE HIGHEST AMOUNTS ACROSS THE
NORTH AND THE LESSER AMOUNTS SOUTH OF INTERSTATE 90.

A VERY STRONG PRESSURE GRADIENT DEVELOPS ON THE BACK SIDE OF THE
SYSTEM AS WELL...WITH NORTH TO NORTHWEST WINDS OF 25 TO 40 MPH
LIKELY BEGINNING ACROSS THE WEST LATE TONIGHT...THEN ACROSS THE
ENTIRE AREA BY TUESDAY AFTERNOON...CONTINUING INTO THE MORNING
HOURS WEDNESDAY. THERE MAY BE A BRIEF PERIOD OF SLEET OR FREEZING
PRECIPITATION ACROSS THE SOUTH TUESDAY MORNING AS WELL...BUT DUE TO
THE EXPECTED BREVITY OF IT...HAVE NOT MENTIONED IT IN THE FORECAST
AT THIS TIME.

WILL SEE LITTLE VARIATION IN TEMPERATURES FROM TONIGHTS LOWS TO
TUESDAYS HIGHS WITH THE CLOUDS AND PRECIPITATION...AND WITH COLDER
AIR BEGINNING TO GET PULLED DOWN ON THE BACK SIDE OF THE STORM. A
BIGGER PUSH OF COLD AIR WILL BEGIN TUESDAY NIGHT AND WILL CONTINUE
THROUGH THE END OF THE PERIOD. DAYTIME HIGHS IN THE SINGLE DIGITS
AND LOWER TEENS WILL BE COMMON WEDNESDAY...WITH SUBZERO LOWS
WEDNESDAY NIGHT.



.LONG TERM...THURSDAY THROUGH MONDAY
THE MAIN STORY DURING THE EXTENDED PERIOD WILL BE THE EXTREMELY
COLD TEMPS THAT FOLLOW THE MID WEEK STORM SYSTEM. ARCTIC COLD AIR
REALLY BEGINS POURING SOUTH ACROSS THE AREA THURSDAY WITH HIGHS IN
THE SINGLE DIGITS ACROSS THE CWA. MODELS HAVE TRENDED A BIT COLDER
DURING THE EXTENDED PERIOD...AND CAN EASILY BUY INTO THIS
ESPECIALLY GIVEN THE FACT THAT IT NOW LOOKS AS IF THERE WILL BE
SOME SNOW ON THE GROUND BY THE END OF THE WEEK. OVERNIGHT LOWS
WILL BE BITTERLY COLD WITH READINGS WELL INTO THE TEENS BELOW
ZERO. MEX GUIDANCE SHOWING -20 FOR ABERDEEN FRIDAY AND SATURDAY
MORNING. IF WE HAVE AT LEAST A FEW INCHES OF SNOW ON THE GROUND BY
THEN...THIS COULD EASILY HAPPEN IF IDEAL RADIATIONAL COOLING
CONDITIONS DEVELOP. MODELS ARE SHOWING AN INVERTED TROUGH SWINGING
ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY WITH SOME ADDITIONAL
SNOW. SO...WILL HAVE TO WATCH WHAT EFFECTS CLOUD COVER MAY HAVE ON
OVERNIGHT LOWS. WILL GO A BIT CONSERVATIVE AT THIS POINT BUT
KEEPING IN MIND THAT FUTURE FORECAST COULD EASILY BE LOWERING
OVERNIGHT LOW TEMPS EVEN MORE...DEPENDING ON THE CLOUD COVER
FORECAST AS WE NEAR THE WEEKEND.





&&

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

SNOW WILL OVERSPREAD THE AREA THROUGH THE NIGHT AND TUESDAY AS
STRONG UPPER LEVEL ENERGY AND WAA MOVES INTO THE REGION. ALL TAF
LOCATIONS ARE EXPECTED TO BE AFFECTED WITH IFR/MVFR CEILINGS AND
VISIBILITIES. NORTH WINDS ARE ALSO EXPECTED TO INCREASE AS THE
SURFACE PRESSURE GRADIENT TIGHTENS UP WITH BLOWING SNOW
DEVELOPING.




&&

.ABR WATCHES/WARNINGS/ADVISORIES...
SD...WINTER STORM WARNING UNTIL 6 PM CST /5 PM MST/ WEDNESDAY FOR
     BROWN-CAMPBELL-CORSON-DEWEY-EDMUNDS-FAULK-MCPHERSON-POTTER-
     WALWORTH.

     WINTER STORM WARNING FROM 6 AM TUESDAY TO 6 PM CST WEDNESDAY FOR
     DAY-MARSHALL-ROBERTS.

     WINTER WEATHER ADVISORY FROM 6 AM CST /5 AM MST/ TUESDAY TO 6 PM
     CST /5 PM MST/ WEDNESDAY FOR BUFFALO-CLARK-CODINGTON-DEUEL-
     GRANT-HAMLIN-HAND-HUGHES-HYDE-JONES-LYMAN-SPINK-STANLEY-
     SULLY.

MN...WINTER STORM WARNING FROM 6 AM TUESDAY TO 6 PM CST WEDNESDAY FOR
     BIG STONE-TRAVERSE.

&&

$$
UPDATE...MOHR
SHORT TERM...PARKIN
LONG TERM...TMT
AVIATION...MOHR

WEATHER.GOV/ABERDEEN