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000
FXUS63 KFGF 190419
AFDFGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
1119 PM CDT TUE JUN 18 2013

.UPDATE...
ISSUED AT 1120 PM CDT TUE JUN 18 2013

WILL ADD THE AVIATION DISCUSSION...BUT NO OTHER UPDATES PLANNED
WITH FORECAST IN GOOD SHAPE THIS EVENING.

&&

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 PM CDT TUE JUN 18 2013

FORECAST CHALLENGE WILL BE TEMPERATURES AND CONVECTIVE POTENTIAL
FROM MIDWEEK AFTER. MODELS CONTINUE WITH SUBTLE DIFFERENCES AND
WILL HANG WITH GENERAL BLEND OF GFS/ECMWF/GEM SOLUTIONS AS NAM
CONTINUES TO BE QUICKEST IN EJECTING PAC NW UPPER LOW EASTWARD.

SURFACE HIGH WILL CONTINUE TO SHIFT ACROSS GREAT LAKES OVERNIGHT
MAINTAINING MODEST WARM ADVECTION AND RETURN FLOW. THIS SHOULD
KEEP TEMPERATURES A FEW DEGREES WARMER THAN LAST NIGHT.

FOR WEDNESDAY UPPER LOW WILL SHIFT INTO THE PACIFIC NW. AS IS DOES
LOW PRESSURE DEEPENS ACROSS NORTHERN HIGH PLAINS. AHEAD OF THE LOW
INCREASING SE FLOW WILL BEGIN TO ADVECT DEEPER MOISTURE N-NW. MOIST
AXIS BECOMES ORIENTED FROM CENTRAL PLAINS NW INTO THE LOW OVER
EASTERN MT. THIS MOIST AXIS WOULD APPEAR TO BE THE FAVORED AREA
FOR CONVECTION DURING THE DAY. FARTHER EAST OVER OUR FA LOW LEVEL
MOISTURE DOES INCREASE ALONG WITH A BROAD AREA OF WARM ADVECTION
BUT LOW/MID LEVEL FORCING SEEMS LIMITED SO DID NOT MAKE ANY GREAT
CHANGES TO POPS BUT OVERALL CONFIDENCE IN POTENTIAL IS LOW. LEANED
TOWARDS WARMER GUIDANCE VALUES BASED ON WARMING COLUMN AND SOLAR
POTENTIAL.

AFTER INITIAL CAPPING FEEL COMPLEX WILL INITIATE LATE EVENING
VCNTY SFC LOW OVER NE MT/NW ND AND PROPAGATE GENERALLY NE INTO
CANADA. MAJORITY OF MODELS COMING INTO BETTER ALIGNMENT IN
DEVELOPING E-W ORIENTED BOUNDARY ALONG ND INTERNATIONAL BORDER
AREA. THIS BOUNDARY COULD BE FOCUS FOR SOME EASTWARD PROPAGATING
CONVECTION SO INCREASED POPS ALONG THE BORDER AREA LATE WEDNESDAY
NIGHT.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 325 PM CDT TUE JUN 18 2013

UNCERTAINTY EVEN GREATER ON THURSDAY. AIRMASS TO BECOME INCREASING
UNSTABLE ACROSS ENTIRE FA. LOW LEVEL FORCING AND FAVORABLE
CONVECTIVE POTENTIAL STILL LOOKS ACROSS THE NORTH NEAR QUASI-
STATIONARY E-W BOUNDARY BUT WHERE THIS ACTUALLY SETS UP WILL
DETERMINE WHERE BRUNT OF CONVECTION WILL BE. IF THIS POSITION
TURNS OUT COMPLEX WILL DEVELOP ACROSS THE NORTH PROPAGATING E-SE
DURING THE EVENING ALONG THICKNESS GRADIENT.

WILL MAINTAIN CHANCE POPS THROUGH FRIDAY HOWEVER COULD BE ANOTHER
ACTIVE DAY BUT MODELS QUITE SPREAD ON SOLUTIONS. COLUMN WILL BE
QUITE WARM THURSDAY INTO FRIDAY WITH DEGREE OF CLOUD COVER
GOVERNING JUST HOW WARM/HUMID WE GET.

FOR FRIDAY NIGHT THRU TUESDAY THE REGION WILL GENERALLY BE IN A
TRANSITION PERIOD. FRI NIGHT INTO SAT NIGHT WILL STILL BE DOMINATED
BY SOUTHWEST FLOW ALOFT. LOOKS LIKE THE BEST CHANCES FOR PCPN MAY BE
FRI NIGHT WITH SOME SORT OF CONVECTIVE COMPLEX FORMING OVER THE AREA
AND TRACKING TO THE EAST. MODELS THEN CLOSE OFF A 500MB LOW OVER THE
WESTERN HIGH PLAINS SUNDAY AND SLOWLY LIFT IT NORTHEAST INTO ONTARIO
MON WHICH WOULD KEEP SOME SCATTERED PCPN CHANCES AROUND. AS THE LOW
PASSES OFF TO THE EAST MORE ZONAL FLOW RETURNS BY TUE. AS FOR TEMPS
THEY LOOK TO REMAIN A LITTLE ABOVE NORMAL WITH HIGHS IN THE 80S.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1120 PM CDT TUE JUN 18 2013

VFR CONDITIONS WILL PREVAIL THROUGH MOST OF THE PERIOD. THERE
COULD BE SOME SHOWERS OR PERHAPS A THUNDERSTORM LATE IN THE
PERIOD...BUT CONFIDENCE NOT HIGH ENOUGH TO MENTION YET.

&&

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

$$

UPDATE...DK
SHORT TERM...VOELKER
LONG TERM...GODON/VOELKER
AVIATION...DK