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000
FXUS63 KFSD 071452
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
852 AM CST FRI MAR 7 2014

.UPDATE...
ISSUED AT 852 AM CST FRI MAR 7 2014

NORTHERN PORTION OF PRECIP HAS DIMINISHED AS EXPECTED...AND HAVE
ALLOWED FREEZING RAIN ADVISORY FOR OUR NORTHEAST TO EXPIRE AT 14Z.
UNFORTUNATELY...ALTHOUGH FREEZING RAIN THIS MORNING WAS NOT THAT
EXTENSIVE...DRIFTING SNOW YESTERDAY AFTERNOON PRODUCED A LAYER OF ICE
ON UNTREATED ROADS THAT WILL HAVE LITTLE CHANCE OF MELTING TODAY AS
TEMPERATURES SLOWLY FALL THROUGH 20S THROUGH THE DAY.

HAVE REWORKED POPS A LITTLE FOR THIS MORNING...AS SOUTHERN PORTION OF
THE BAND BEGINNING TO REACH THE GROUND IN A FEW AREAS. DO NOT EXPECT
THIS BAND TO AMOUNT TO MUCH...BUT AREAS SOUTH OF I-90 COULD SEE A
HUNDREDTH OR TWO. MORNING MODELS HAVING SOME DIFFICULT AGREEING ON
WHETHER PRECIP WILL BECOME HEAVIER THAN EXPECTED. HRRR AND NAM ARE
LARGELY DRY...WHILE RAP PRODUCES UP TO A TENTH OF AN INCH. THE LATTER
SEEMS OVERDONE BASED ON CURRENT CONDITIONS HOWEVER...SO WILL CONTINUE
WITH DRIER THINKING FOR NOW.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CST FRI MAR 7 2014

A COLD FRONT WILL WORK ITS WAY ACROSS THE AREA TODAY. TEMPERATURES
THIS MORNING IN THE 30S...WILL FALL INTO THE 20S THROUGH THE DAY.
CURRENTLY SEEING A LIGHT AREA OF PRECIPITATION ALONG THE
BOUNDARY...BUT EXPECTATION IS THAT THIS WILL BE IN A WEAKENING
STATE AS IT MOVES INTO THE DRY LOW AND MID LEVELS OVERHEAD. WILL
CONTINUE TO CARRY SOME LOW POPS...BUT IF ANYTHING DOES OCCUR AMOUNTS
WILL BE VERY LIGHT...WITH THE BEST CHANCE THIS MORNING ALONG THE
HIGHWAY 14 CORRIDOR INTO SOUTHWEST MINNESOTA. PRECIPITATION TYPE
THIS MORNING WOULD EITHER BE LIGHT RAIN OR LIGHT FREEZING RAIN. AS
WE HEAD INTO THIS AFTERNOON...THE FRONT PUSHES SOUTH OF INTERSTATE
90...AND A WAVE BEGINS TO EJECT OUT OF THE ROCKIES. THE INTERACTION
OF THIS FRONT AND WAVE COULD ALLOW THE PRECIPITATION COVERAGE TO
INCREASE SOME SOUTH OF INTERSTATE 90 THIS AFTERNOON AND EVENING.
ALTHOUGH THE HI RES MODELS ARE TRENDING TOWARDS A DRY
SOLUTION...SHOWING THE DRY AIR WINNING OUT. THUS WILL CONTINUE TO
ONLY CARRY CHANCE POPS. ANYTHING THAT DOES FALL WOULD INITIALLY BE
RAIN OR SLEET...BEFORE COLD AIR MOVES IN AND CHANGES THINGS TO LIGHT
SNOW. BUT AGAIN...NOT SURE WE EVEN SEE ANYTHING...AND IF WE DO
AMOUNTS WOULD BE LIGHT...WITH ONLY A COATING OF SNOW.

WINDS WILL BE BLUSTERY TODAY OUT OF THE NORTH BEHIND THE FRONT...15
TO 25 MPH WITH SOME HIGHER GUSTS. THIS COULD BE ENOUGH TO ALLOW FOR
SOME MORE BLOWING AND DRIFTING OF THE SNOW ON THE GROUND IN
SOUTHWEST MINNESOTA. WINDS ARE PROBABLY TOO LIGHT FOR SIGNIFICANT
VISIBILITY REDUCTIONS...WITH DRIFTING SNOW BEING THE MAIN POTENTIAL
ISSUE. SKIES BEGIN TO CLEAR TONIGHT...BECOMING MOSTLY TO PARTLY
CLEAR BY MORNING. PRETTY GOOD AGREEMENT AMONG THE GUIDANCE ON
LOWS...MAINLY SINGLE DIGITS AND TEENS ABOVE ZERO...WITH A FEW SPOTS
POTENTIALLY AROUND OR JUST BELOW ZERO FROM BROOKINGS INTO SOUTHWEST
MINNESOTA. WITH THE NORTHERLY BREEZE...WIND CHILLS WILL DROP INTO
THE 5 BELOW TO 15 BELOW ZERO RANGE EAST OF THE JAMES RIVER.

.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 347 AM CST FRI MAR 7 2014

MAIN FOCUS IN THE EXTENDED IS ON TEMPERATURES...AND PRECIP CHANCES
ON TUESDAY AS UPPER LEVEL WAVE BEHIND A COLD FRONT MOVES THROUGH THE
REGION THROTTLING BACK TEMPERATURES.

ON SATURDAY...WARM FRONT BEGINS TO PROGRESS ACROSS THE AREA.  AHEAD
OF THE FRONT...WINDS REMAIN FAIRLY WEAK AND WITH DEEP SNOW COVER
ACROSS THE EAST...SIDED WITH HIGHS CLOSE TO ISOTHERMAL FROM 925
HPA.  MODELS SHOW A BATCH OF HIGH CLOUDS MOVING IN FROM THE
NORTH...WHICH IF THICK ENOUGH COULD HAMPER WARMING SOMEWHAT.  FRONT
CONTINUES TO SHIFT EAST ON SATURDAY NIGHT INTO SUNDAY WITH FAIRLY
SUBSTANTIAL WARMING ALOFT.  THIS SHOULD TRANSLATE WELL TO AREAS THAT
HAVE LIMITED SNOW COVER...BUT IN AREAS FURTHER EAST FOLLOWED SNOW
CLIMATOLOGY FOR HIGHS WHICH WAS VERY CLOSE TO GOING FORECAST.  STILL
APPEARS TO BE A FAIR AMOUNT OF HIGH CLOUDS HANGING AROUND ON SUNDAY
AS WELL THAT COULD LIMIT WARMING SOME.

WITH WEST TO SOUTHWEST FLOW...EXPECT SNOW PACK TO DWINDLE ACROSS THE
SOUTHWESTERN HALF OF THE FORECAST AREA SUNDAY INTO MONDAY.  WITH 925
HPA TEMPS WARMING INTO THE TEENS...COULD BE A NICE MILD DAY ACROSS
THE REGION...THOUGH THERE IS SOME QUESTION OF FOG POTENTIAL ACROSS
THE AREA. THERE IS CERTAINLY A STRONG INVERSION ALOFT...AND WITH
MELTING SNOW PACK SHOULD BE PLENTY OF NEAR SURFACE MOISTURE TO LEAD
TO SATURATION.  QUESTION THOUGH AS TO WHETHER THE WINDS ALOFT ARE
STRONG ENOUGH TO KEEP THE NEAR SURFACE LAYER MIXED ENOUGH TO LIMIT
FOG POTENTIAL. FOR NOW...LEFT OUT OF THE FORECAST BUT WILL NEED SOME
WATCHING.

COLD FRONT MOVES THROUGH THE AREA AND SURFACE TEMPERATURES WILL BE
CRITICAL IN TERMS OF PRECIPITATION TYPE.  AS OF RIGHT NOW..APPEARS
AS THOUGH MOISTURE WOULD BE SOMEWHAT LIMITED WITH BRIEF SATURATION.

THEREAFTER...APPEARS AS THOUGH ANOTHER WARMING TREND
ENSUES...HOWEVER...LOWERED FORECAST HIGHS IN THE EAST DUE TO DEEP
AND LIKELY REMAINING SNOW PACK.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 539 AM CST FRI MAR 7 2014

MVFR CIGS WILL MOVE INTO THE AREA BEHIND A COLD FRONT THIS MORNING.
COULD BE A LITTLE LIGHT ICING AS WELL THIS MORNING...ALTHOUGH THE
GREATEST THREAT OF THIS WILL REMAIN NORTH OF INTERSTATE 90. COULD
ALSO BE A LITTLE LIGHT SNOW THIS AFTERNOON AND EVENING AROUND
KSUX...BUT PROBABILITY IS TOO LOW TO MENTION IN THE TAFS AT THIS
TIME. EXPECT THE MVFR CIGS TO STICK AROUND FOR MUCH OF THE
DAY...SLOWLY CLEARING FROM NORTH TO SOUTH TONIGHT. CONFIDENCE IS LOW ON
THE EXACT DEPARTURE TIME OF THE CLOUDS AND THE RETURN TO VFR...SO
FUTURE SHIFTS WILL NEED TO MONITOR TRENDS AND TRY TO BETTER PIN THAT
DOWN. WINDS WILL BE BLUSTERY OUT OF THE NORTH TODAY...GUSTING 20 TO
30 KTS...BEFORE DECREASING TONIGHT.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&

$$

UPDATE...JH
SHORT TERM...CHENARD
LONG TERM...
AVIATION...CHENARD