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000
FXUS63 KBIS 261433
AFDBIS

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

.UPDATE...
ISSUED AT 923 AM CDT SAT JUL 26 2014

GOING FORECAST IN PRETTY GOOD SHAPE WITH LOW PASSING TO THE NORTH
OF THE AREA WITH WINDS CONTINUING TO INCREASE. ONLY CHANGE WAS TO
ADJUST CLOUD COVER UP A BIT OVER NORTHERN ZONES AS IT WORKS IN
BEHIND AFOREMENTIONED LOW. UPDATES HAVE BEEN SENT.

UPDATE ISSUED AT 633 AM CDT SAT JUL 26 2014

HRRR MODEL SO FAR CORRECTLY FORECAST SURFACE TROUGH PASSAGE AND
BAND OF CLOUDS ACROSS THE SOUTH CENTRAL. BELIEVE THIS FEATURE
WILL REMAIN DRY WITH SCATTERED SHOWERS SOUTH IN SOUTH DAKOTA. TO
THE NORTH...UPPER LEVEL LOW WILL BRING INCREASING NORTHWEST WINDS
AND SCATTERED SHOWERS TO THE NORTH TODAY. CURRENT FORECAST LOOKS
GOOD.

&&

.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 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 633 AM CDT SAT JUL 26 2014

GUSTY WEST TO NORTHWESTERLY WINDS BETWEEN 25KT AND 35KT WILL OCCUR
ACROSS THE TERMINALS BEGINNING AROUND 15Z AND CONTINUING THROUGH 02Z
SUNDAY. SATELLITE IMAGERY SHOWS LOW VFR/MVFR CIGS OVER SOUTHERN
SASKATCHEWAN. THIS WILL IMPACT KISN/KMOT FROM 16Z SATURDAY THROUGH
02Z SUNDAY. KMOT WILL HAVE THE HIGHEST PROBABILITY OF -SHRA AND
BRIEF PERIODS OF MVFR CIGS WHICH WILL BE COVERED IN A TEMPO GROUP
BETWEEN 18Z AND 22Z SATURDAY. THE REST OF THE TERMINALS WILL REMAIN
VFR.


&&

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

$$

UPDATE...JJS
SHORT TERM...KS
LONG TERM...WAA
AVIATION...WAA