FXUS63 KFGF 010820

AFDFGF



AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE GRAND FORKS ND

320 AM CDT SUN AUG 1 2010



.DISCUSSION...



PRECIP CHANCES CONTINUE TO BE THE MAIN FORECAST CONCERN.



RECENT RADAR TRENDS HAVE TWO PERSISTENT AREAS OF PRECIP OVER

ND...ONE OVER THE SOUTH CENTRAL PORTIONS OF THE STATE ALONG THE

NOSE OF THE LOW LEVEL JET...WHILE ANOTHER AREA OF SHOWERS AND

THUNDERSTORMS HAS ENTERED NORTHWESTERN ND WITH THE MAIN SHORTWAVE

RIDING OVER THE TOP OF THE UPPER RIDGE. HOW THIS CONVECTION

EVOLVES WILL HAVE A LARGE EFFECT ON HOW THINGS DEVELOP LATER THIS

AFTERNOON. THE HRRR HAS THE SOUTHERN AREA OF PRECIP DIMINISHING AS

IT ENTERS OUR SOUTHERN COUNTIES TOWARDS EARLY MORNING...WHICH

WOULD FIT WITH A WEAKENING LOW LEVEL JET. THE NAM AND GFS HOLD

ONTO THE PRECIP A BIT LONGER. LINGERING CLOUDS COULD LIMIT LOW

LEVEL HEATING IN CERTAIN AREAS...BUT MODELS ARE IN PRETTY GOOD

AGREEMENT ON AT LEAST A FEW AREAS OF THE CWA GETTING TO 2000 J/KG

THIS AFTERNOON...ALTHOUGH THEY DISAGREE ON WHERE. WITH 40-60 KTS

OF BULK SHEAR AND THE INSTABILITY...CHANCES ARE PRETTY GOOD OF

SEVERE WEATHER SOMEWHERE IN THE CWA. GOING FORECAST HAS 40 BLANKET

POPS BEFORE 00Z...AND GIVEN THE UNCERTAINTY AS TO HEATING/OUTFLOW

BOUNDARIES...AM RELUCTANT TO CHANGE THIS TOO MUCH. WILL KEEP AN

EYE ON RADAR TRENDS AND MAY BUMP THEM UP A BIT THIS MORNING.



TONIGHT...THERE IS BETTER AGREEMENT ON PRECIP DEVELOPING ACROSS

OUR SOUTH TO SOUTHEASTERN CWA AS THE SFC TROUGH BEGINS TO MOVE

EAST...BRINGING THE WINDSHIFT LINE/WEAK BOUNDARY INTO THAT AREA.

PWAT VALUES AGAIN GET ABOVE 2 INCHES SO HEAVY RAIN WILL AGAIN BE

POSSIBLE OVERNIGHT. THE WEAK SFC BOUNDARY WILL SHIFT A BIT FURTHER

SOUTHEAST ON MONDAY...BUT SOME LINGERING ACTIVITY NEAR IT COULD

KEEP A SLIGHT CHANCE FOR THUNDERSTORMS GOING IN OUR SOUTHEAST. THE

NAM AND GFS ALSO BREAK OUT A BIT IN OUR NORTH AS THE MAIN UPPER

SHORTWAVE MOVES ACROSS SOUTHERN MANITOBA...SO INCLUDED SOME LOW

POPS IN THAT AREA FOR MONDAY.  



TUESDAY THROUGH THURSDAY...THE NORTHERN PLAINS SHOULD SEE NEAR

ZONAL FLOW ALOFT. THE GFS TRANSITIONS THIS TO NORTHWESTERLY AS IT

DIGS A FAIRLY SIGNIFICANT SHORTWAVE INTO MN

WEDNESDAY/THURSDAY...ALTHOUGH IT SEEMS TO BE AN OUTLIER. EVEN WITH

THE ZONAL FLOW...WEAK SHORTWAVES COMING THROUGH COULD SET OFF

PRECIP...BUT SUCH FEATURES ARE NOISE AT THIS POINT AND MODELS DO

NOT HAVE ENOUGH OF A HANDLE ON TIMING TO PUT ANY POPS INTO THE

FORECAST AT THIS POINT.



&&



.AVIATION...



WITH HIGH LEVEL CLOUDS INHIBITING RADIATIVE COOLING DOWN TO THE

DEWPOINT...CONDITIONS SHOULD REMAIN VFR THROUGH MUCH OF THE

MORNING AND INTO THE AFTERNOON. CONVECTION MOVING INTO THE REGION

IS UNCERTAIN ENOUGH TO COVER WITH VCTS/CB MENTION. DEPENDING ON

IF THERE IS ANY CLEARING LATE TONIGHT IN AREAS THAT RECEIVED

PRECIP...MAY HAVE TO WATCH EASTERN TAF SITES FOR FOG FORMATION

AFTER 06Z.



&&



.FGF WATCHES/WARNINGS/ADVISORIES...

ND...NONE.

MN...NONE.

&&



$$

JR