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000
FXUS63 KFSD 312332
AFDFSD

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SIOUX FALLS SD
632 PM CDT THU JUL 31 2014

.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 258 PM CDT THU JUL 31 2014

SCATTERED TO BROKEN CLOUD COVER OUT THERE THIS AFTERNOON...SOME FROM
DIURNALLY DRIVEN CU...AND SOME MID LEVEL ACCAS WITH A WEAK WAVE
SINKING SOUTH. A FEW ISOLATED SHOWERS AS WELL...MAYBE A RUMBLE OF
THUNDER...BUT NOT MUCH MORE THAN THAT EXPECTED. SHOULD BECOME MOSTLY
CLEAR OVERNIGHT WITH LOWS IN THE MID TO UPPER 50S UNDER NEARLY CALM
WINDS.

FRIDAY WILL PROBABLY END UP SIMILAR TO TODAY. ANOTHER WEAK LOW LEVEL
WAVE WILL DROP SOUTH...BUT SUBSIDENCE ALOFT IS PRETTY
STRONG...LIKELY LIMITING SHOWER DEVELOPMENT. EITHER WAY...THINKING
WE SEE A MIX OF CU AND ACCAS MAKING IT A PARTLY CLOUDY SKY. CAN NOT
RULE OUT A FEW ISOLATED SHOWERS AND MAYBE THUNDERSTORM...SO WILL
CARRY SOME LOW POPS. ALTHOUGH TIMING AND 850 MB TEMPERATURES WARM
SLIGHTLY OVER TODAY...SO WILL HIGHS WILL PROBABLY END UP A BIT
WARMER...ABOUT 79 TO 82 EAST OF INTERSTATE 29 AND THE LOW TO MID 80S
WEST.

.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 258 PM CDT THU JUL 31 2014

SEASONAL TEMPERATURES CAN BE EXPECTED OVER WHAT SHOULD BE A PRETTY
NICE WEEKEND. MARGINAL INSTABILITY TO THE SOUTH AND WEST OF THE CWA
MAY SUPPORT ISOLATED SHOWERS AND THUNDERSTORMS ALONG THE MISSOURI
RIVER VALLEY...BUT MOST AREAS WILL REMAIN DRY. SOUTHEAST FLOW SHOULD
BE COMMON WITH GUSTS IN MOST AREAS AT 15 TO 20 MPH OR LESS DURING
THE AFTERNOON HOURS. LOWS MAINLY IN THE UPPER 50S TO LOWER 60S WITH
HIGHS MAINLY IN THE 80S.

IN THE OUTER PERIODS(MONDAY THROUGH THURSDAY)...UPPER LEVEL RIDGING
WILL TRY TO BUILD INTO THE AREA THROUGH THE PERIOD BUT IS LIKELY TO
BE SUPPRESSED BY A STRENGTHENING TROUGH OVER SOUTHERN CANADA. A WEAK
WAVE MOVES OVER THE TOP OF THE RIDGE ON MONDAY AND SHOULD BRING A
GOOD CHANCE FOR THUNDERSTORMS DURING THIS TIME. IF THE MODELS ARE
CORRECT INSTABILITY WILL BE PRETTY GOOD...CAP VALUES OF ABOUT 3000
J/KG BUT SHEAR IS MARGINAL. SO...AN ISOLATED THREAT FOR SEVERE
STORMS. THE BOUNDARY WILL STILL BE LINGERING ON TUESDAY SO THE
CHANCE FOR STORMS WILL CONTINUE AND POSSIBLY BECOME A LITTLE BETTER
ON TUESDAY. SUSPECT THAT MONDAY AND TUESDAY WILL BE A BIT HUMID WITH
NEAR TO ABOVE NORMAL TEMPERATURES WHILE WEDNESDAY INTO THURSDAY WILL
SEE BELOW NORMAL TEMPERATURES.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 631 PM CDT THU JUL 31 2014

ISOLATED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DOT THE
FORECAST AREA INTO EARLY THURSDAY EVENING...MAINLY ALONG AND SOUTH
OF I 90. THE ACTIVITY IS TOO ISOLATED TO PUT IN THE TAF SITES.
OTHERWISE LIGHT WINDS WILL PREVAIL WITH VFR CONDITIONS
ANTICIPATED TONIGHT AND FRIDAY. A REPEAT OF ISOLATED SHOWERS AND
STORMS WILL OCCUR FRIDAY AFTERNOON...BUT AGAIN THE THREAT IS TOO
ISOLATED TO MENTION IN THE TAF SITES AT THIS TIME.

&&

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

$$

SHORT TERM...CHENARD
LONG TERM...08
AVIATION...MJ