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000
FXUS63 KBIS 260821
AFDBIS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BISMARCK ND
321 AM CDT SAT JUL 26 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 322 AM CDT SAT JUL 26 2014

THE LATEST SATELLITE IMAGERY SHOWS A COMPACT CLOSED UPPER LOW
CIRCULATING OVER SOUTHEAST SASKATCHEWAN. A 1003MB SURFACE LOW WAS
LOCATED OVER WYNYARD SASKATCHEWAN...DIRECTLY BENEATH THE UPPER LOW.
AS A RESULT...THE LOW CONTINUES TO FILL/WEAKEN WITH TIME. ATTACHED
TO THE LOW IS A COLD FRONTAL BOUNDARY EXTENDING FROM SOUTHEAST
SASKATCHEWAN INTO MINOT AND GARRISON...AND CONTINUING SOUTH TO
GLEN ULLIN AND HETTINGER. COLD AIR ADVECTION TODAY COMBINED WITH A
DECENT PRESSURE GRADIENT SETTING UP FROM EASTERN MONTANA TO
NORTHWEST MINNESOTA WILL RESULT IN WINDY CONDITIONS. AS IS USUALLY
THE CASE...INCLUDING TODAYS DATA...THE MET/NAM WIND GUIDANCE IS
WEAKER THAN THE MAV/GFS. THE LATEST RAP13 AND ECMWF FAVORS THE
LOWER END OF STRONGEST WINDS. THIS ULTIMATELY SUGGESTS A WEAK
CONFIDENCE LEVEL FOR A WIND ADVISORY. WOULD LIKE TO MORE AGREEMENT
AMONGST THE FORECAST DATA WITH HIGHER SUSTAINED WINDS. THUS HAVE
DECIDED TO HOLD OFF ON ISSUING A WIND ADVISORY AS IT REMAINS
MARGINAL AT THIS TIME. THE DAY SHIFT CAN HAVE ANOTHER LOOK AS WINDS
INCREASE BY MID/LATE MORNING TO COMPARE ACTUAL VERSUS FORECAST.

OTHERWISE THE LATEST FOG/STRATUS LOOP SHOWS A LARGE SWATH OF
LOW/MID LEVEL BKN/OVC CLOUDS ASSOCIATED WITH THE SURFACE/UPPER LOW
CIRCULATION OVER SOUTHERN SASKATCHEWAN. THESE ARE NOW BEGINNING TO
CROSS THE NORTHWEST CORNER OF THE STATE. THE HRRR SHOWS THIS BAND
OF CLOUDS ARCING INTO WILLISTON AND MINOT BETWEEN 16Z-17Z. THERE
WILL BE AN AREA OF ISOLATED TO SCATTERED RAINSHOWERS AND ISOLATED
THUNDERSTORMS OVER THE NORTH CENTRAL TODAY. THE NAM WAS MOST
AGGRESSIVE IN GENERATING PRECIPITATION INTO SOUTH CENTRAL NORTH
DAKOTA THIS AFTERNOON. BUT WITH ALL OTHER MODELS MAINTAINING THE
THREAT OVER THE NORTH...HAVE DISCOUNTED THE NAM AND CONTINUED/REFINED
WITH WHAT THE PREVIOUS FORECAST HAD. HIGHS TODAY IN THE NORTH WITH
MOSTLY CLOUDY/WINDY/WET CONDITIONS WILL REACH THE UPPER 60S.
IN THE CENTRAL AND SOUTH...EXPECT MOSTLY SUNNY AND WINDY WEATHER
WITH HIGHS AROUND 80.

ALSO...SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER CENTRAL AND
NORTHERN SOUTH DAKOTA ALONG AND NORTH OF A LOW LEVEL CONVERGENCE
FIELD/FRONTAL BOUNDARY. THERE IS SOME HINT PER RAP13 THAT SHOWERS
WILL ENTER FAR SOUTHERN NORTH DAKOTA THROUGH 15Z SATURDAY. WILL
CONTINUE TO MONITOR THIS AND ADJUST AT THE LAST MINUTE IF TRENDS
CONTINUE TO SHOW DEVELOPMENT FARTHER NORTH.

.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 322 AM CDT SAT JUL 26 2014

THE EXTENDED PERIOD BEGINS THE AN UPPER LOW OVER SOUTH CENTRAL
CANADA THAT WILL MOVE SOUTHEAST AND MERGE INTO A LARGE HUDSON BAY
TROUGH SETTING UP A BLOCKING PATTERN ACROSS EASTERN NORTH AMERICA
WHICH WILL MAINTAIN A RIDGE OVER THE WESTERN US AND A TROUGH OVER
THE EAST. THE NORTHERN PLAINS WILL BE IN FOR A PERIOD OF QUIET
WEATHER FOR THIS EXTENDED PERIOD. FOR THE FIRST PORTION OF THE
FORECAST...SUNDAY THROUGH WEDNESDAY...EXPECT MAINLY DRY WEATHER
WITH A SLOW WARMING TREND. HIGHS IN THE UPPER 60S TO MID 70S ON
SUNDAY WILL MODERATE TO THE LOWER TO MIDDLE 80S BY WEDNESDAY
THROUGH FRIDAY. WITH THE H500 RIDGE FIRMLY IN PLACE OVER THE
WESTERN US ONLY A FEW WEAK IMPULSES MAY BE ABLE TO DRIFT ACROSS
THE NORTHERN PLAINS. FOR THIS POSSIBILITY LEFT WIDELY SCATTERED
CHANCES FOR THUNDERSTORMS WEDNESDAY WITH THURSDAY AND FRIDAY
BASICALLY DRY AND WARM.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 322 AM CDT SAT JUL 26 2014

MAIN THEME TODAY WILL BE GUSTY WEST TO NORTHWESTERLY WINDS BETWEEN
25KT AND 35KT ACROSS THE TERMINALS. THESE WINDS WILL ABATE BY 02Z
SUNDAY. ALSO...LOW VFR/MVFR CIGS OVER SOUTHERN SASKATCHEWAN WILL
SAG INTO NORTHERN NORTH DAKOTA. THIS WILL IMPACT KISN/KMOT FROM
16Z SATURDAY THROUGH 02Z SUNDAY WITH LOW VFR CONDITIONS MIXED IN
WITH BRIEF PERIODS OF MVFR. THE REST OF THE TERMINALS WILL REMAIN VFR.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...KS
LONG TERM...WAA
AVIATION...KS