943 
FXUS63 KFSD 160901
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
401 AM CDT SAT MAR 16 2013

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 357 AM CDT SAT MAR 16 2013

COLD AIR CONTINUES TO FILTER IN FROM THE NORTH BEHIND THE COLD FRONT 
THAT PASSED THROUGH THE AREA EARLIER. DRIER LOW LEVEL AIR IS ALSO MAKING 
PROGRESS SOUTH...AND EXPECT LOW STRATUS TO DISSIPATE FROM NORTH TO 
SOUTH THROUGH THE MORNING. HOWEVER MID AND HIGH LEVEL MOISTURE WILL 
REMAIN HIGH...AND THUS PARTLY TO MOSTLY CLOUDY SKIES ARE STILL 
LIKELY THROUGH THE DAY. EXPECT IT TO BE A CHILLY DAY...WITH HIGHS 
RANGING FROM THE LOW 20S NORTH TO THE MID 30S SOUTH...ABOUT 10 TO 20 
DEGREES BELOW NORMAL. WEAK WAVE PASSES THROUGH TONIGHT...BUT MAINLY 
JUST EXPECTING CLOUDS WITH THIS SYSTEM...WITH BEST LIFT STAYING 
SOUTH AND WEST OF THE CWA...AND SOME DRY AIR OVERHEAD. WITH THAT 
SAID...SOME OF THE NEWER GUIDANCE IS SUGGESTING MAYBE SOME LIGHT 
SNOW FOR A PERIOD TONIGHT WEST OF THE JAMES RIVER IN SOUTH CENTRAL 
SD...SO IF THINGS LOOK BETTER ON THE DAY SHIFT THEY MAY HAVE TO ADD 
IN SOME LIGHT SNOW ACROSS THAT AREA...ALTHOUGH WOULD THINK ONLY A 
COATING WOULD FALL. OTHERWISE...LOWS TONIGHT SHOULD RANGE FROM THE 
SINGLE DIGITS NORTHEAST TO AROUND 20 SOUTHWEST.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 357 AM CDT SAT MAR 16 2013

RETURN SOUTHERLY FLOW INCREASES ON SUNDAY OUT AHEAD OF AN 
APPROACHING UPPER TROUGH...ADVECTING IN WARMER LOW LEVEL TEMPERATURE 
PROFILES. THUS WE SHOULD SEE HIGHS SEVERAL DEGREES WARMER THAN 
TODAY...MAINLY 30S AND LOWER 40S. SOUTHERLY JET IS PRETTY 
STRONG...25 TO 35 KTS AT 925MB...AND GUIDANCE SUGGESTING WE MAY 
APPROACH WIND ADVISORY CRITERIA WEST OF THE JAMES RIVER. THE TROUGH 
AXIS SWINGS THROUGH ON SUNDAY NIGHT...WITH THE SURFACE LOW PASSING 
TO OUR NORTH INTO EASTERN NORTH DAKOTA AND THE TRAILING COLD FRONT 
MOVING THROUGH OVERNIGHT. MODELS IN PRETTY GOOD AGREEMENT ON THE 
SYNOPTIC SETUP SUNDAY NIGHT INTO MONDAY. FORCED ASCENT AHEAD OF THE 
TROUGH AXIS COMBINED WITH DECENT ISENTROPIC LIFT SHOULD SET THE 
STAGE FOR A PERIOD OF PRECIPITATION SUNDAY NIGHT ACROSS THE CWA. 
SEEMS LIKE QPF AMOUNTS OF 0.1 TO 0.2 INCHES ARE A GOOD BET...HOWEVER 
PTYPE IS STILL UNCERTAIN. QUITE A BIT OF WARM AIR AROUND 925MB TO 
THE SURFACE WILL ADVECT IN AHEAD OF THE PRECIP FROM THE SOUTHWEST. 
COLD AIR WILL QUICKLY MOVE IN BY LATER SUNDAY NIGHT...HOWEVER 
THINKING MOST OF THE PRECIP FALLS AHEAD OF THE COLD AIR. BEST CHANCE 
OF SEEING ALL SNOW WILL BE ACROSS SOUTHWEST MINNESOTA AND PORTIONS 
OF NORTHWEST IOWA...WHICH WILL BE FURTHEST FROM THE WARM AIR 
INTRUSION. SOUTH CENTRAL SD MAY END UP BEING MOSTLY RAIN...WHILE 
LOCATIONS IN BETWEEN THESE AREAS...INCLUDING SIOUX FALLS...SEE A 
RAIN SNOW MIX CHANGING OVER TO SNOW...AS BORDERLINE BOUNDARY LAYER 
TEMPERATURES DYNAMICALLY COOL ENOUGH TO CHANGE THINGS OVER TO SNOW. 
OVERALL THINKING SNOW AMOUNTS OF AROUND 1 TO 2 INCHES WHERE SNOW IS 
THE PREDOMINATE PTYPE.

WINDS WILL REALLY PICK UP BEHIND THE FRONTAL PASSAGE SUNDAY 
NIGHT...WITH ABOUT 30 TO 35 KTS AT 925 MB ON MONDAY. THUS 
NORTHWESTERLY WINDS AROUND ADVISORY LEVEL...25 TO 35 MPH WITH GUSTS 
TO 45 MPH...SEEM LIKELY MONDAY OVER MOST OF THE CWA. WITH THE 
SURFACE LOW TRACKING WELL TO OUR NORTH...THINKING MOST OF THE 
WRAPAROUND SNOW WILL REMAIN TO OUR NORTH. HOWEVER SCATTERED SNOW 
SHOWERS SEEM PROBABLE ACROSS THE NORTHEAST HALF OF THE 
AREA...ESPECIALLY DURING THE MORNING. WHILE NOT MUCH IF ANY 
ACCUMULATION IS EXPECTED...THE SNOW SHOWERS COMBINED WITH THE STRONG 
WINDS COULD CREATE AREAS OF REDUCED VISIBILITY. ALSO MAY SEE THE 
SNOW THAT FALLS SUNDAY NIGHT BLOW AROUND SOME...ALTHOUGH WITH IT 
BEING MORE OF A WETTER SNOW AND ONLY SMALL AMOUNTS EXPECTED...DONT 
THINK BLOWING OF THE GROUND SNOW WILL BE TOO BAD.

TEMPERATURES LOOK TO STAY BELOW NORMAL RIGHT THROUGH NEXT 
WEEK...WITH HIGHS MAINLY IN THE 20S AND 30S...AND LOWS IN THE TEENS. 
THE NEXT SYSTEM TO WATCH FOR IS THURSDAY...AS A PACIFIC WAVE MOVES 
INTO THE PLAINS. PTYPE WITH THIS SYSTEM WOULD BE MAINLY SNOW WITH 
COLD AIR IN PLACE. HOWEVER MODEL TRENDS HAVE BEEN TO KEEP MOST OR 
ALL OF THE PRECIP WITH THIS SYSTEM TO OUR SOUTH...WITH A LARGE 
NORTHERN STREAM CUTOFF LOW SUPPRESSING THE SYSTEM. THE GFS IS 
FURTHEST NORTH AND GIVES THE CWA SOME DECENT SNOW...HOWEVER WITH THE 
EC AND GEM BOTH SOUTH...WOULD LEAN IN THAT DIRECTION. BUT GIVEN 
UNCERTAINTY WILL LEAVE THE ALLBLEND CHANCE POPS THURSDAY INTO FRIDAY 
FOR NOW.  


&&

.AVIATION...(FOR THE 16/06Z TAFS THROUGH 17/06Z) ISSUED AT 1055 PM 
CDT FRI MAR 15 2013

CEILINGS BLO 1K FEET OVER ALL OF THE AREA WILL IMPROVE SLOWLY FROM 
THE NORTH TO 1-2K FEET 10Z-16Z. VISIBILITIES 3-5SM IN LIGHT FOG WITH 
AREAS VISIBILITY BELOW 3SM IN FOG WEST OF HON/YKN LINE WILL IMPROVE 
SLOWLY TO ABOVE 5SM FROM THE NORTH 09Z-15Z. ISOLATED PATCHES OF 
-FZDZ POSSIBLE IN FOGGY AREAS. AFTER 16Z LOW CLOUDS WILL DECREASE 
FROM THE WEST THROUGH 17/00Z WITH CEILINGS BECOMING AOA 10K FEET. 
VFR CONDITIONS SHOULD THEN CONTINUE OVER THE AREA 17/00Z-06Z.


&&

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

$$

SHORT TERM...CHENARD
LONG TERM...CHENARD