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000
FXUS63 KFSD 221122
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
622 AM CDT TUE JUL 22 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 421 AM CDT TUE JUL 22 2014

A FRONTAL BOUNDARY CONTINUES TO SETTLE SOUTHWARD THIS
MORNING...BRINGING SLIGHTLY COOLER AND DRIER AIR SOUTHWARD.  ALONG
AND AHEAD OF THIS BOUNDARY...SEEING VISIBILITY RESTRICTIONS DEVELOP
AND WILL INCLUDE A MENTION OF FOG AHEAD OF THE BOUNDARY THROUGH
DAYBREAK AS IT MOVES SOUTHEAST.  WE`RE ALSO WATCHING A WEAK MID-LEVEL
SHORTWAVE CROSSING THE DAKOTAS THIS MORNING.  HIGH-RES ARW/NMM SEEM
TO HAVE A REASONABLE HANDLE ON THIS PRECIPITATION...SUGGESTING THAT
UNDER CURRENT TRAJECTORIES THE SHORTWAVE WILL MOVE ACROSS THE CWA
THROUGH MID-MORNING...AND PRECIPITATION WILL GRADUALLY WANE AS IT
REACHES THE MN/SD STATE LINE. QPF AMOUNTS WILL BE RATHER LIGHT GIVEN
THE SPOTTY NATURE OF THE ACTIVITY.

ASIDE FROM MORNING SHOWERS...QUIET WEATHER IS ANTICIPATED FOR THE
REMAINDER OF TUESDAY AS WELL AS TUESDAY NIGHT.  HIGH PRESSURE SINKING
SOUTHWARD WILL BRING DRIER AIR INTO THE REGION WITH TEMPERATURES
RISING INTO THE LOWER TO MIDDLE 80S.  TONIGHT...FALLING DEW POINTS
WILL ALSO LEAD TO FALLING TEMPERATURES AS READINGS BOTTOM OUT IN THE
LOWER 60S.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 421 AM CDT TUE JUL 22 2014

SURFACE RIDGE MOVING THROUGH THE CWA ALONG WITH UPPER RIDGE AXIS
JUST TO OUR WEST SHOULD KEEP THE AREA DRY DURING THE DAY WEDNESDAY.
TEMPERATURES WILL BE A SHADE ON THE ON COOL SIDE OF NORMAL...WITH
UPPER 70S EAST TO MID 80S WEST ALONG WITH COMFORTABLE HUMIDITY
LEVELS. STRONG WARM ADVECTION DEVELOPS INTO OUR WEST WEDNESDAY NIGHT
AS THE SURFACE RIDGE SHIFTS EAST. ELEVATED INSTABILITY ALONG WITH
LOW LEVEL JET FROM WESTERN NEBRASKA INTO WESTERN/CENTRAL SOUTH
DAKOTA SHOULD SUPPORT ELEVATED STORMS WEST OF I-29 PRIOR TO DAYBREAK
THURSDAY. THIS ACTIVITY EXPECTED TO SHIFT EAST ACROSS THE FORECAST
AREA THROUGH THE DAY...BUT ANTICIPATE WEAKENING/DECREASE IN COVERAGE
AS IT WORKS INTO DRIER AIR MASS STILL IN PLACE ACROSS IOWA/MINNESOTA
IN THE WAKE OF DEPARTING SURFACE RIDGE.

RENEWED DEVELOPMENT EXPECTED ACROSS OUR EAST THURSDAY NIGHT AS
DEEPER MOISTURE SHIFTS EAST AHEAD OF SURFACE CYCLOGENESIS OVER THE
WESTERN PLAINS. 40-50KT LOW LEVEL JET AIDING THE STRONG MOISTURE
TRANSPORT INTO THE AREA...AS WELL AS STRONG WARM ADVECTION ACROSS
OUR EAST THURSDAY EVENING. CURRENTLY APPEARS HEAVIEST OVERNIGHT
RAINS WILL BE JUST EAST OF OUR FORECAST AREA...THOUGH PLACEMENT
SOMEWHAT UNCERTAIN GIVEN MODEL DIFFERENCES IN TIMING/LOCATION OF
SURFACE LOW AND MID LEVEL WAVE. DO NOT ANTICIPATE MUCH OF A SEVERE
THREAT EITHER NIGHT. DECENT DEEP LAYER SHEAR PER THE MODELS...BUT
MUCH OF THIS WILL BE UNTAPPED GIVEN EXPECTED ELEVATED NATURE OF
STORMS.

SMALL CHANCE OF STORMS LINGERING ACROSS OUR NORTHEAST INTO FRIDAY
AND FRIDAY NIGHT AS UPPER WAVE DROPS SOUTHEAST INTO MINNESOTA...
THOUGH CONFIDENCE LOW IN THIS PERIOD WITH LITTLE AGREEMENT AMONG THE
VARIOUS MODELS. SOMEWHAT BETTER AGREEMENT THROUGH THE LATTER PART OF
THE FORECAST...WITH UPPER TROUGH STILL ON TRACK TO ROTATE SOUTHEAST
THROUGH THE UPPER MIDWEST/GREAT LAKES ON SUNDAY. COULD SEE A FEW
SHOWERS OR THUNDERSTORMS BRUSH OUR EASTERN AREAS WITH THIS...BUT
OTHERWISE DRY CONDITIONS WILL DOMINATE THE WEEKEND INTO EARLY NEXT
WEEK. TEMPERATURES WILL BE SEASONABLE TO SLIGHTLY COOL FOR LATE
JULY...WITH FRIDAY/FRIDAY NIGHT THE MOST HUMID PERIOD OF THE LONGER
RANGE...FOLLOWED BY WHAT APPEARS TO BE A MORE PROLONGED STRETCH OF
MORE COMFORTABLE DEW POINTS IN THE MID 50S TO MID 60S.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 619 AM CDT TUE JUL 22 2014

DECAYING SHOWERS WILL DISSIPATE QUICKLY THIS MORNING AS SLIGHTLY
DRIER AIR FILTERS SOUTHEAST. WE`LL WATCH FOR MVFR STRATUS TO FILTER
SOUTHWARD AS WELL BEHIND THE DEPARTING FRONT...GRADUALLY LIFTING INTO
VFR LEVELS BY MID-DAY.

WINDS WILL REMAIN NORTHERLY THROUGH THE OVERNIGHT HOURS...WITH VFR
CONDITIONS INTO WEDNESDAY MORNING.

&&

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

$$

SHORT TERM...DUX
LONG TERM...JH
AVIATION...DUX