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000
FXUS63 KFSD 262009
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
309 PM CDT SAT JUL 26 2014

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 307 PM CDT SAT JUL 26 2014

MORNING CONVECTION HAS FINALLY MOVED SOUTH OF THE CWA THIS
AFTERNOON. ATTENTION NOW TURNS TO THE ARRIVAL OF THE CANADIAN FRONT
WHICH WILL MOVE THROUGH THE CWA THIS EVENING.  STABLE AIR BEHIND
MORNING CONVECTION WILL PREVENT MUCH IN THE WAY OF RENEWED
THUNDERSTORMS ALONG THE BOUNDARY. SLIGHT CHANCE WILL REMAIN IN THE
FAR NORTH...WHERE A NARROW CU FIELD CONTINUES TO DEVELOP AND SFC
CONVERGENCE IS SLIGHTLY ENHANCED.

TONIGHT...A FRONTAL BOUNDARY WILL PUSH THROUGH THE CWA BY
MIDNIGHT...WITH MUCH DRIER AIR POURING SOUTHWARD. WINDS ARE EXPECTED
TO TURN NORTHWEST WITH A SLIGHT BREEZE INTO SUNDAY MORNING.

SUNDAY....UPPER LOW CROSSING NORTHERN MINNESOTA WILL ENTER THE
WESTERN GREAT LAKES BY SUNDAY MORNING. BY EARLY AFTERNOON WE WILL
MIX FAIRLY DEEP...AOA 800 MB...WHICH SHOULD RESULT IN A WIDESPREAD
CU FIELD.  DOWNWARD MOMENTUM TRANSFER WILL FAVOR 15-20 KNOT AFTN
MID-AFTERNOON WINDS. CAN`T RULE OUT A FEW SPRINKLES/VERY LIGHT RAIN
SHOWERS IN THE FAR EAST.  AS FAR AS TEMPERATURES ARE
CONCERNED...SUNDAY WILL BE THE BEGINNINGS OF AN EXTENDED PERIOD OF
SLIGHTLY BELOW NORMAL TEMPERATURES. HIGHS WILL STRUGGLE TO REACH THE
MID-UPPER 70S.

.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 307 PM CDT SAT JUL 26 2014

THE EXTENDED PORTION OF THE FORECAST WILL BE CHARACTERIZED BY BELOW
NORMAL TEMPERATURES AND DRIER THAN AVERAGE PRECIPITATION. A PRETTY
AMPLIFIED AND STAGNANT PATTERN WILL PERSIST THROUGH THE WEEK...WITH
AN UPPER TROUGH OVER THE EASTERN PORTION OF THE COUNTRY AND RIDGING
TO THE WEST. OUR CWA WILL THUS REMAIN IN NORTHWEST FLOW AND ON THE
COOLER SIDE OF THE THERMAL RIDGE. WINDS WILL GENERALLY BE PRETTY
LIGHT...AND SKIES PARTLY TO MOSTLY SUNNY...WITH JUST SOME DIURNALLY
DRIVEN CU. DOES NOT APPEAR TO BE MUCH IN THE WAY OF UPPER FORCING IN
THE NORTHWEST FLOW...SO DESPITE THE COOL TEMPERATURES ALOFT...LOOKS
LIKE WE SHOULD STAY DRY. CAN NOT COMPLETELY RULE OUT AN ISOLATED
SHOWER OR THUNDERSTORM SOMETIME LATER IN THE WEEK...BUT CONFIDENCE
TOO LOW TO INTRODUCE ANYTHING INTO THE FORECAST.

FOR HIGHS...GFS IS A WARM OUTLIER...WITH THE ECMWF...NAM AND GEM
KEEPING SLIGHTLY COOLER TEMPERATURES ALOFT. ALTHOUGH THE DRY LOW
LEVELS SHOULD ALLOW US TO MIX WELL AND FULLY REALIZE THE TEMPERATURES
ALOFT. THUS CONSENSUS AND BIAS CORRECTED CONSENSUS VALUES LOOKED
PRETTY GOOD THROUGH THE PERIOD. MONDAY AND TUESDAY WILL BE THE
COOLEST...MID 70S TO LOW 80S...WITH A BIT WARMER READINGS OF MAINLY
LOW TO MID 80S BY LATER IN THE WEEK. LOWS WILL BE CHILLY AS
WELL...AND WENT ON THE COOLER SIDE OF GUIDANCE SUNDAY NIGHT THROUGH
TUESDAY NIGHT. AS CLEAR SKIES AND LIGHT WINDS SHOULD ALLOW FOR PRETTY
GOOD RADIATIONAL COOLING. LOOKING AT LOW TO MID 50S ACROSS MOST OF
THE AREA THOSE NIGHTS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1234 PM CDT SAT JUL 26 2014

CONVECTION IS SLOWLY MOVING AWAY FROM THE TERMINALS EARLY THIS
AFTERNOON...WITH KSUX BEING IMPACTED WITHIN THE UPCOMING HOUR WITH A
BRIEF MVFR REDUCTION POSSIBLE. OTHERWISE...VFR CONDITIONS SHOULD PREVAIL FOR
THE MAJORITY OF AFTERNOON AS THE TRUE COLD FRONT MOVES THROUGH.

MOSTLY CLEAR SKIES THROUGH THE NIGHT WITH DRY AIR FILTERING
SOUTHWARD.


&&

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

$$

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