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000
FXUS63 KUNR 151656
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1056 AM MDT TUE APR 15 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
ISSUED AT 324 AM MDT TUE APR 15 2014

WATER VAPOR IMAGERY SHOWS A HIGH AMPLITUDE TROUGH CROSS THE
MISSISSIPPI VALLEY...WITH STRONG RIDGING CONTINUING TO BUILD ACROSS
THE NORTHERN PLAINS. A STRONG SERIES OF WAVES ARE PUSHING INTO THE
NORTHERN PACIFIC COAST...WHICH WILL BE A FOCUS FOR PRECIPITATION THE
NEXT COUPLE DAYS. SURFACE ANALYSIS SHOWS HIGH PRESSURE IN CONTROL
ACROSS THE DAKOTAS INTO THE UPPER MIDWEST. A WARM FRONT IS
STRADDLING THE CWA...WITH TEMPS IN NE WY IN THE MID TO UPPER
30S...WHILE THE CNTRL SD PLAINS ARE IN THE TEENS TO LOWER 20S.

DRY WEATHER WILL CONTINUE THROUGH THE DAY TODAY. WITH HIGH PRESSURE
PUSHING EASTWARD...AND RETURN FLOW SETTING UP OVER THE CWA...THE
WARM FRONT WILL SHIFT TO THE NE AS WARMER AIR ADVECTS IN. TEMPS
TODAY WILL BE MUCH WARMER WITH HIGHS IN THE MID 50S TO MID 60S.

CLOUDS WILL INCREASE THROUGH THE AFTERNOON AS THE PACIFIC SHORTWAVE
CROSSES THE NORTHERN ROCKIES. SURFACE LOW PRESSURE WILL CROSS ERN MT
AND CROSS INTO SD THIS EVENING. A COLD FRONT WILL CROSS THE CWA THIS
EVENING WITH PRECIP DEVELOPING ACROSS THE AREA TONIGHT. MODELS ARE
STILL HAVING TROUBLE RESOLVING DETAILS WITH THE PRECIP TONIGHT INTO
WEDNESDAY. LATEST RUNS ARE NOW SHOWING THE PRECIP FARTHER SOUTH
AFTER 06Z TONIGHT...AFFECTING MOSTLY THE SD PLAINS SOUTH OF THE
INTERSTATE INTO SCNTRL SD. WENT WITH THE SREF FOR PRECIP TYPE...WITH
PRECIP STAYING AS RAIN ACROSS THE PLAINS FOR MUCH OF THE NIGHT THEN
MIXING WITH OR CHANGING TO SNOW ACROSS NE WY AND MUCH OF THE SD
PLAINS EXCEPT SCNTRL SD. PRECIP WILL CHANGE TO SNOW OVER THE HIGHER
ELEVATIONS OF THE BLKHLS SOONER THIS EVENING. QPF AMOUNTS HAVE BEEN
DIFFICULT TO FORECAST...BUT FOR NOW WILL GO WITH 1-3 INCH
ACCUMULATION WORDING FOR THE BLKHLS. THE PLAINS COULD SEE AN INCH OR
SO OF ACCUMULATION. THE FRONTAL BOUNDARY WILL STALL ACROSS ERN/CNTRL
WY WITH AN ACTIVE UPPER LEVEL PATTERN CONTINUING. THIS WILL BRING
CONTINUED CHANCES FOR RAIN OR SNOW OVER THE AREA...WITH THE BEST
CHANCES OVER NE WY...THE BLKHLS AND SW SD. LITTLE TO NO ACCUMULATION
IS EXPECTED...EXCEPT MAYBE AN INCH OVER THE HILLS. LESSER CHANCES
FOR PRECIP WILL CONTINUE INTO WED NIGHT AS UPPER WAVES CONTINUE TO
PUSH THROUGH.


&&

.LONG TERM...THURSDAY THROUGH MONDAY
ISSUED AT 324 AM MDT TUE APR 15 2014

UPPER LEVEL SHORTWAVE ROTATES THROUGH THE DAKOTAS ON
THURSDAY...WITH DECENT Q-VECTOR CONVERGENCE AND STEEP MID LEVEL
LAPSE RATES. 03Z SREF IS NOW SHOWING 40-60% POPS ACROSS WESTERN
SOUTH DAKOTA ON THURSDAY. HAVE TRENDED POPS UPWARD FOR THURSDAY.
WITH CLOUDS AND PRECIPITATION...WENT SLIGHTLY LOWER THAN GUIDANCE
FOR HIGH TEMPERATURES. NEXT UPPER LEVEL SHORTWAVE QUICKLY MOVES
ACROSS THE AREA FRIDAY NIGHT...BRINGING SOME LIGHT RAIN/SNOW. FLAT
UPPER RIDGE THEN BUILDS INTO THE PLAINS FOR THE WEEKEND AND EARLY
NEXT WEEK...WITH DRY WEATHER AND MUCH WARMER TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY)
ISSUED AT 1051 AM MDT TUE APR 15 2014

VFR CONDITIONS WILL CONTINUE THROUGH THIS AFTN. A CDFNT WILL MOVE
THROUGH THE AREA TONIGHT. WDSPRD MVFR/IFR CIGS WILL DEVELOP BEHIND
THE CDFNT ALONG WITH GUSTY NW WINDS. RAIN WILL ALSO DEVELOP
TONIGHT...CHANGING TO SNOW OVER NERN WY AND THE BLKHLS LATE
TONIGHT...WITH A RAIN/SNOW MIX POSSIBLE VERY LATE TONIGHT ON THE
SD PLAINS. IFR CONDITIONS IN SNOW EXPECTED OVER NERN WY AND THE
NRN BLKHLS FROM LATE TONIGHT INTO WED MRNG.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...13
LONG TERM...7
AVIATION...JOHNSON