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000
FXUS63 KFGF 162018
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
318 PM CDT SUN JUN 16 2013

.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 315 PM CDT SUN JUN 16 2013

FORECAST CHALLENGE CONCERNS TEMPERATURES AND PCPN CHANCES. MODELS
IN REASONABLE AGREEMENT THROUGH THE PERIOD AND WILL USE A BLEND.

UPPER LOW OVER S SASK/MB BORDER AREA TO WEAKEN AND DROP THROUGH FA
OVERNIGHT INTO EARLY MONDAY. FOR THIS EVENING EXPECT WHAT
SHRA/ISOLD T DO DEVELOP TO DIMINISH THROUGH EVENING ESPECIALLY
AFTER LOSS OF HEATING. FUTURE SHIFT WILL NEED TO MONITOR ANY
DEVELOPMENT ACROSS SD WHICH MAY CLIP SOUTHERN ZONES. CLOUD TRENDS
A LITTLE TRICKY OVERNIGHT AS MID LEVEL SHEAR AXIS DROPS THROUGH. WITH
CELLULAR NATURE OF CLOUDS EXPECT SOME OF THIS TO DISSIPATE BUT
COULD BE SOME LINGERING CLOUDS VCNTY UPPER TROUGH. COLD ADVECTION
TO CONTINUE OVERNIGHT BUT UPSTREAM DEWPOINTS BEHIND COLD FRONT NOT
MUCH DIFFERENT CURRENT VALUES SO MINIMUM TEMPERATURES SHOULD NOT
DROP OFF TO FAR FROM AVERAGE VALUES.

DEEPER LAYERED MOISTURE IN VCNTY OF PASSING TROUGH...COLD POOL AND LOWER
CONVECTIVE TEMPERATURES SHOULD RESULT IN PLENTY OF CLOUD COVER AND
SCT SHRA/ISOLD T FOR MONDAY. WITH CLOUDS TEMPERATURES WILL BE
QUITE A BIT COOLER.

ANY SHOWERS AGAIN TO DIMINISH DURING THE EVENING. WITH HIGH
PRESSURE OVERHEAD BY MORNING...CLEARING AND COOLER COLUMN SOME
AREAS COULD SEE MINIMUMS IN THE 40S BUT LIKELY WILL HINGE ON CLOUD
COVER.



.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 315 PM CDT SUN JUN 16 2013

HIGH PRESSURE SHIFTS EAST TUESDAY FOR RETURN FLOW/WARM ADVECTION
SET UP. MODELS DIFFER ON ANY RAIN POTENTIAL BUT WITH LACK OF
FORCING MOST AREAS LOOK DRY. TEMPERATURES SHOULD RECOVER BACK TO
AT OR ABOVE AVERAGE.

AN UNSETTLED PERIOD SETTING UP FOR LATE THIS WEEK INTO NEXT WEEKEND.
12 UTC GFS/ECMWF SYNOPTIC DETAILS IN FAIR AGREEMENT...BOTH SHOWING A
SHORT-WAVE RIDGE MOVING ACROSS THE NORTHERN PLAINS. WHILE INITIALLY
UNDER THE INFLUENCE OF NORTHWEST FLOW ALOFT...THE RIDGE AXIS BECOMES
ALIGNED ALONG THE RED RIVER VALLEY BY 12 UTC FRIDAY ALLOWING MOIST
SOUTHWEST FLOW TO IMPACT THE REGION THROUGH THE WEEKEND.

WITH 48 PLUS HOURS OF MOIST SOUTHERLY FLOW ALONG AN 850 HPA 30 KT
JET BEGINNING THURSDAY MORNING...INSTABILITY PARAMETERS SOAR TO
EXTREME LEVELS BY 00 UTC SATURDAY WITH MLCAPE OF 3000 PLUS J/KG AND
LIFTED INDICIES FROM -10 TO -12. THIS IS A RESULT OF MODELED SURFACE
DEW POINT VALUES FROM 65 TO 75 DEGREES. SURFACE MOISTURE OF THIS
MAGNITUDE IS OVERDONE...ESPECIALLY GIVEN THE LATE START TO THE
GROWING SEASON AND LESS EVAPOTRANSPIRATION THAN NORMAL FOR THIS TIME
OF YEAR. HOWEVER...GIVEN OVERALL SYNOPTIC PATTERN...THINK DEW POINTS
IN THE LOWER TO MID 60S ARE A REAL POSSIBILITY. THE STRONGEST DEEP
LAYER SHEAR REMAINS WEST OF THE FORECAST AREA THROUGH THURSDAY AND
700 HPA TEMPERATURES ARE INITIALLY +12 TO +14 C BEFORE DROPPING LATE
FRIDAY NIGHT AND SATURDAY WITH PASSAGE OF A COLD FRONT. DESPITE
POSSIBLE CAPPING AND FORCING LIMITATIONS...SEVERE CONVECTION IS A
CONCERN AND WILL NEED TO WATCH THIS CAREFULLY THROUGH THE WEEK.

VERY DIFFICULT AT THIS TIME TO PINPOINT AREAS OF FAVORED SHOWERS AND
THUNDERSTORMS VERSUS DRY CONDITIONS...SO WILL FOLLOW ALL BLEND POPS
FOR NOW WHICH PAINT THE FORECAST AREA WITH 30 TO 60 PERCENT FOR MUCH
OF THE PERIOD. TEMPERATURES WILL BE IN THE 70S TO LOWER 80S FOR
HIGHS AND UPPER 50S AND 60S FOR LOWS.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1219 PM CDT SUN JUN 16 2013

SCT-BKN CU FROM 4-8 KFT AGL TO DEVELOP THIS AFTERNOON AHEAD OF A
LOW PRESSURE SYSTEM ACROSS SOUTHERN CANADA. SOME SHOWERS AND
ISOLATED EMBEDDED THUNDERSTORMS ARE POSSIBLE MAINLY ALONG AND NORTH
OF THE HIGHWAY 2 CORRIDOR THROUGH 01-02 UTC. WILL KEEP VICINITY
MENTION AT KDVL/KGFK/KTVF/KBJI DUE TO TIMING AND COVERAGE
UNCERTAINTY. BREEZY WEST-NORTHWEST WINDS WITH GUSTS FROM 20 TO 30
KTS WILL PERSIST THROUGH THE AFTERNOON...DECREASING AFTER SUNSET.

EVOLUTION OF CLOUD COVER AND ASSOCIATED CEILINGS IN QUESTION
OVERNIGHT. AS LOW PRESSURE CENTER MOVES INTO THE MN ARROWHEAD AND
NORTHWEST WI OVERNIGHT...SOME MVFR CEILINGS MAY MOVE ACROSS EASTERN
ND AND NORTHWEST MN. CONFIDENCE NOT HIGH ENOUGH GIVEN MODEL RH
VARIATIONS...BUT SOMETHING TO WATCH.


&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&

$$

SHORT TERM...VOELKER
LONG TERM...ROGERS/VOELKER
AVIATION...ROGERS