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000
FXUS63 KFSD 252109
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
309 PM CST WED FEB 25 2015

.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 310 PM CST WED FEB 25 2015

ONE LAST AREA OF FLURRIES AND LIGHT SNOW PUSHING ACROSS THE AREA
THIS AFTERNOON. ONLY WILL SEE A COUPLE TENTHS AT MOST WITH THIS...SO
A MAJORITY OF THE ACCUMULATING SNOW HAS ENDED. ALREADY SEEING SOME
CLEARING WORK IN FROM THE NORTH...AND THIS TREND WILL CONTINUE
THROUGH THE NIGHT. THUS SHOULD EVENTUALLY BECOME MOSTLY CLEAR. MAIN
STORY WILL BE THE VERY COLD WIND CHILLS TONIGHT INTO THURSDAY
MORNING. A NORTHERLY BREEZE STAYING UP WILL KEEP US MIXED ENOUGH TO
PREVENT THE BOTTOM FROM DROPPING OUT OF TEMPERATURES...BUT STILL
LOOKING AT LOWS IN THE SINGLE DIGITS BELOW ZERO. COMBINE THIS WITH
THE WIND AND EXPECTING WIND CHILLS IN THE -20 TO -30 RANGE. THUS
WILL ISSUE A WIND CHILL ADVISORY FOR ALL BUT SOUTH CENTRAL
SD...WHERE READINGS WILL BE A BIT HIGHER.

SLOW WARMING ON THURSDAY...SO WIND CHILLS ADVISORY WILL GO THROUGH
18Z. EVEN IN THE AFTERNOON WIND CHILLS WILL LINGER IN THE -10 TO -20
RANGE...SO STILL QUITE COLD. HIGHS WILL ONLY BE IN THE SINGLE DIGITS
AND TEENS. ALTHOUGH DID BUMP THEM UP A BIT...MAINLY ALONG THE
MISSOURI RIVER CORRIDOR WHERE LESS SNOW FELL. SKIES SHOULD BE MOSTLY
SUNNY...ALTHOUGH SIGNS THAT SOME AFTERNOON STRATOCU MAY TRY TO
DEVELOP MAKING IT PARTLY CLOUDY BY AFTERNOON.


.LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 310 PM CST WED FEB 25 2015

THURSDAY NIGHT WILL BRING THE LATEST ARCTIC HIGH RIGHT OVER THE AREA
WITH CLEAR SKIES AND LIGHT WINDS. TEMPERATURES WILL DROP WELL BELOW
ZERO WITH LOWS 17 BELOW EAST TO 6 BELOW SOUTHWEST. WINDS FOR ONCE
ARE GOING TO DROP LOW ENOUGH...TO NEAR CALM...TO MAKE THE WIND CHILL
A NON FACTOR...IT WILL JUST BE PLAIN COLD.

SOME UPPER RIDGING WILL DEVELOP OVER THE AREA FRIDAY AS THE SURFACE
HIGH VERY SLOWLY MOVES EAST OF THE AREA. SKIES WILL STAY
CLEAR/MOSTLY CLEAR AND TEMPERATURES WILL REBOUND TO MOSTLY THE 10 TO
20 DEGREE RANGE.

FRIDAY NIGHT AND SATURDAY WILL BRING AN INCREASE IN CLOUDS IN A
DEVELOPING WARM ADVECTION PATTERN. TEMPERATURES WILL
WARM...ESPECIALLY ON LOWS. THERE MAY BE ENOUGH LIFT WITH A WEAK
SHORT WAVE IN DEVELOPING WEST SOUTHWESTERLY UPPER FLOW TO BRING SOME
LIGHT SNOW TO THE AREA SOUTHEAST OF FSD LATE SATURDAY AFTERNOON AND
SATURDAY NIGHT. A NORTHWESTERLY UPPER WAVE AND FOLLOWING SURFACE
HIGH WILL SUPPRESS THE THERMAL GRADIENT TO THE SOUTH ALONG WITH SOME
COOLING ON SUNDAY...ALTHOUGH WITH THE LAG IN SURFACE WARMING
SATURDAY...SUNDAY HIGHS WILL BE NEARLY THE SAME.

THE MORE INTERESTING POTENTIAL DEVELOPS MONDAY THROUGH TUESDAY AS
WAVE/S EJECTING NORTHEAST OUT OF SOUTHWESTERN UPPER LOW POSITION
BRING A SNOW THREAT AS THE THERMAL GRADIENT RETURNS TO PRIME
POSITION. THE GFS IS THE STRONGEST AND WOULD SUGGEST A DECENT SNOW
BY MONDAY NIGHT...BUT THE EC IS COMING AROUND TO SOMETHING CLOSER
THAN WAS ON LAST NIGHTS RUN. OTHER MODELS SUCH AS THE UKMET SUGGEST
SOME SNOW POTENTIAL WITH PERHAPS LATER TIMING. EXTENDED GUIDANCE
LOOKS GOOD FOR NOW WITH NO NEED TO PUT MUCH FAITH IN THE SMALLER
DETAILS 5 TO 6 DAYS AHEAD. ANYWAY...THERE IS POTENTIAL FOR RIDGING
OVER THE SOUTHERN PLAINS TO SET UP A VERY GOOD MOISTURE INFLOW TO
ADVECT ACROSS THE AFOREMENTIONED THERMAL PATTERN. TEMPERATURES
MONDAY AND TUESDAY WILL BE MODERATELY COLD...WITH READING WHICH
WOULD HAVE BEEN A TAD ABOVE NORMAL A FEW WEEKS AGO BUT WOULD BE ON
THE OTHER SIDE NOW AS WE APPROACH MARCH.

WILL GO WITH THE EXTENDED GUIDANCE IDEA OF DRY AND A BIT COOLER
WEDNESDAY...COUNTING ON ANOTHER CANADIAN SHORT WAVE TO SUPPRESS
FURTHER ACTION TRYING TO APPROACH FROM THE SOUTHWEST.


&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1156 AM CST WED FEB 25 2015

SNOW CONTINUES TO DISSIPATE ACROSS THE AREA. ALTHOUGH PERIODS OF
VIS IN THE 2 TO 5 MILE RANGE WILL CONTINUE UNTIL MID AFTERNOON.
MVFR CIGS WILL CLEAR FROM NORTH TO SOUTH TONIGHT. TOUGH CALL ON
THE TIMING OF RETURN TO VFR...WITH SOME MODELS DEVELOPING MORE
STRATUS. HOWEVER BASED ON UPSTREAM VFR OBS WENT OPTIMISTIC IN THE
TAFS...AND TAKE THINGS VFR PRETTY QUICKLY LATER THIS AFTERNOON AND
EVENING. WILL NEED TO MONITOR TRENDS AND ADJUST AS NEEDED.


&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
     FOR SDZ038>040-052>056-059>062-065>071.

MN...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
     FOR MNZ071-072-080-081-089-090-097-098.

IA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
     FOR IAZ001>003-012>014-020>022-031-032.

NE...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON CST THURSDAY
     FOR NEZ013-014.

&&

$$

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