000
FXUS63 KFSD 131727
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1227 PM CDT THU MAR 13 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 408 AM CDT THU MAR 13 2014

A NICE WARM DAY AHEAD BUT NO RECORDS WILL BE BROKEN. THE NEXT WEEK
OR SO WILL SEE SEVERAL RECORD OR NEAR RECORD HIGHS AND LOWS FROM
2012 WHICH ENDED UP BEING THE WARMEST MARCH ON RECORD. WENT AHEAD
AND RAISED HIGHS TODAY AS THERE IS LITTLE CLOUD COVER EXPECTED WITH
DRY AIR THROUGH THE COLUMN OF AIR ON THE AREA SOUNDINGS. SO GOING TO
SHOOT FOR UPPER 60S TO LOWER 70S DOWN THE JAMES RIVER VALLEY INTO
PARTS OF NORTHWEST IOWA BUT COOL HIGHS OFF INTO THE MID 50S OVER
PARTS OF SOUTHWEST MINNESOTA WHERE THE GROUND IS A LITTLE WETTER AND
SOME SNOW COVER STILL EXISTS. NO MAJOR FIRE WEATHER CONCERNS BUT THE
SOUTH CENTRAL ZONES WILL SEE WINDS OF ABOUT 10 TO 20 MPH WITH
AFTERNOON RELATIVE HUMIDITIES NEAR 20 PERCENT...SO SOMETHING TO KEEP
IN MIND IF THE WIND ENDS UP A LITTLE STRONGER THAN EXPECTED.

A TROUGH OF LOW PRESSURE WILL PASS TONIGHT AND SHOULD KEEP WINDS
MIXED THROUGH THE NIGHT. WEAK TO MODERATE COLD AIR ADVECTION SHOULD
BRING THE SLIGHTLY STRONGER WINDS THROUGH BEFORE MIDNIGHT THEN
EXPECT WINDS TO SETTLE TO SOMETHING CLOSER TO 10 TO 12 MPH OR SO
AFTER MIDNIGHT. WITH THE WIND AND A FEW CLOUDS AROUND TEMPERATURES
WILL BE MILD AND MAINLY IN THE LOWER TO MIDDLE 30S ON FRIDAY MORNING.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 408 AM CDT THU MAR 13 2014

FRIDAY CERTAINLY TO BE A MIXY DAY WITH CYCLONIC FLOW AND BROAD
WEAK COLD AIR ADVECTION CONTINUING ACROSS THE AREA. A SECONDARY
FRONT WILL SETTLE SOUTHWARD INTO THE AREA LATE DAY...BUT LIKELY
WILL ONLY ENHANCE MIXING AHEAD OF THE BOUNDARY. WINDS MAINLY
NORTHWEST AT A 15 TO 30 MPH RANGE. COULD SEE A FEW MORE LOWER
CLOUDS WANDERING SOUTHWARD IMMEDIATELY BEHIND THE BOUNDARY...BUT
TEMPS DO NOT LOOK COOL ENOUGH ALOFT TO WARRANT A CHANCE FOR ANY
FLURRIES AND PROBABLY WARM ENOUGH TO GET LOWER TO MID 40S
NORTHEAST AND LOWER TO MID 50S THROUGH THE MISSOURI
VALLEY...PERHAPS SNEAKING INTO AN EARLIER FALL ACROSS THE FAR
NORTH/NORTHEAST BY MID AFTERNOON.

COOLER AIR WILL CONTINUE TO OOZE SOUTHWARD THROUGH FRIDAY NIGHT...
BUT BOUNDARY SHOULD BE SLOWED BY UPPER IMPULSES WORKING TOWARD THE
WESTERN PLAINS. A LITTLE FRONTAL SQUEEZE WORKS OUT ACROSS NORTHERN
PORTIONS OF THE CWA LATER ON FRIDAY NIGHT BETWEEN EXITING GREAT
LAKES JET AND THE ELEVATED WARM ADVECTION WITH THE APPROACHING
WAVE. INTRODUCED A SMALL CHANCE FOR LIGHT SNOWFALL FOR FRIDAY
NIGHT INTO SATURDAY MORNING ACROSS AREAS NORTHEAST OF A HURON TO
SPENCER IOWA LINE...NORTH OF WHERE THE LOWER LEVEL THERMAL
BOUNDARY LOOKS TO STALL OUT FOR THE BRIEF TIME. THIS BOUNDARY
WILL GET A DECENT KICK AS UPPER WAVE MOVES PAST EARLY IN THE DAY...
SO WILL SEE TENDENCY FOR SOMEWHAT LIMITED TEMP RISES...ESPECIALLY
NORTH.

COLDER AIR DRIVES SOUTHWARD THROUGH SATURDAY NIGHT AND EARLY
SUNDAY WITH SURFACE RIDGE PUSHING THROUGH MINNESOTA AND WISCONSIN.
STRONGER SOUTHERLY GRADIENT WILL DEVELOP IN THE AFTERNOON. LIKELY
TO FIND A CONSIDERABLE EAST/WEST GRADIENT IN TEMPS ON SUNDAY...
EVEN WITH THE EXPECTED FAIR AMOUNT OF CLOUDS BY LATER IN THE DAY.
FOR NOW...WARM ADVECTION ZONE WORKING BACK EASTWARD ALOFT IS
LIKELY TO PRODUCE MINIMAL PRECIPITATION...MAINLY DURING THE LATER
AFTERNOON OR EVENING...AND WILL KEEP MAINLY AS LIGHT SNOWFALL WITH
PRECIP EXPECTED TO END BEFORE TEMPS ALOFT WARM TOO MUCH TO CREATE
ALTERNATE TYPE.

CONFIDENCE LEAVES THE LONGER RANGE FORECAST FAIRLY SIGNIFICANTLY
AS IT SEEMS LONGER RANGE MODELS CONTINUE TO HAVE SIGNIFICANT
PREDICTABILITY ISSUES HEADING INTO NEXT WEEK. GFS IS A LOWER
AMPLITUDE AND QUICK WITH FEATURES...ECMWF SLOWER AND MORE
AMPLIFIED...AND CANADIAN SOMEWHAT MODEST IN BETWEEN. GIVEN THAT
GFS IS AT ODDS WITH A SIGNIFICANT PORTION OF A VERY DIVERSE
ENSEMBLE...AND THAT STATISTICAL GFS ENSEMBLE GUIDANCE SIDES TOWARD
A COOLER AND PERHAPS MORE PRECIPITATION LADEN FORECAST... HAVE
TAKEN AT LEAST A HALF STEP TOWARD THE EC SOLUTION. WOULD CERTAINLY
BE LOOKING AT MUCH HIGHER PRECIPITATION CHANCES BY TUESDAY GIVEN
ANY SOLUTION IN THE NEIGHBORHOOD. HAVE BEEN FAIRLY BROAD IN PRECIP
THREAT AND TYPE AT THIS POINT...AND TEMPERATURES ARE PROBABLY A
BIT LESS VARIABLE THAN THEY MAY BE EARLY NEXT WEEK. COULD BE QUITE
A STRONG THERMAL GRADIENT ON MONDAY DEPENDING ON WHERE LEADING
WARM FRONT SETS UP...WITH POTENTIAL FOR SOME READINGS CLOSER TO
MID TO UPPER 60S TO THE SOUTH OF BOUNDARY...AND PERHAPS CLOUDS AND
PRECIP HOLDING TEMPS TO 30S TO THE NORTH. CERTAINLY WILL SEE AN
EVOLUTION IN THIS PERIOD AS THE DAYS GO BY...

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1227 PM CDT THU MAR 13 2014

VFR EXPECTED OVER THE FORECAST AREA THROUGH 14/18Z. SURFACE GUSTS
FROM THE NORTHWEST OF 25 TO 30 KNOTS POSSIBLE AFTER 14/15Z.

&&

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

$$

SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...