Flash Flooding and Hail in Minnesota, August 16 to 18, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
835 PM CDT TUE AUG 16 2005

FORECAST CHALLENGE CONCERNS T CHANCES AND TEMPERATURES.

WDLY SCT CONVECTION CONTINUES TO INITIATE ALONG E-W ORIENTED
BOUNDARY OVER FAR SOUTHERN FA. WITH LACK OF LOW LEVEL JET...LOSS OF
SURFACE HEATING AND UPPER SUPPORT EXPECT STORMS TO GRADUALLY
DIMINISH TOWARDS SUNSET. MAIN CONVECTIVE SHOW CURRENTLY OVER
NORTHERN HIGH PLAINS VCNTY SFC LOW...ASSOCIATED N-S BOUNDARY AIDED
BY APPROACHING SHORTWAVE ENERGY AND RELATED INCREASING WARM
ADVECTION. RUC APPEARS TO HAVE GOOD HANDLE ON SITIUATION. LOW LEVEL
JET INCREASES TO NEAR 40KTS OVER WESTERN/CENTRAL ND AND WARM
ADVECTION INCREASES AND SPREADS EAST TOWARDS FA LATE...MAINLY ACROSS
NORTHERN FA. THIS SHOULD KEEP CONVECTION PROPAGATING EAST AND WILL
MAINTAIN CURRENT POPS/T WORDING HOWEVER WILL DELAY ANY ARRIVAL UNTIL
LATE TONIGHT AS T YET TO ENTER W ND. AS WARM FRONT LIFTS SLOWLY
NORTH OVERNIGHT HIGHER DEWPOINTS SHOULD HOLD TEMPERATURES UP.
FARTHER NORTH WITH LOW DEWPOINTS COULD SEE RELATIVELY QUICK DROP
BEFORE CLOUDS LEVEL OFF TEMPERATURES. WILL MAKE SOME MINOR
ADJUSTMENTS ACROSS SOUTH OTHERWISE NO BIG CHANGES TO TEMPERATURES.
&&

.AVIATION...EXPECT VFR CONDITIONS TONIGHT INTO WEDNESDAY WITH POCKETS
OF MVFR CIGS/ VSBYS LATER TONIGHT/WEDNESDAY IN CONJUNCTION WITH
STRONGER CONVECTION.

&&

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

VOELKER

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GRAND FORKS ND
303 PM CDT TUE AUG 16 2005

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-172015-
WEST POLK-NORMAN-CLAY-KITTSON-ROSEAU-LAKE OF THE WOODS-
WEST MARSHALL-EAST MARSHALL-NORTH BELTRAMI-PENNINGTON-RED LAKE-
EAST POLK-NORTH CLEARWATER-SOUTH BELTRAMI-MAHNOMEN-
SOUTH CLEARWATER-HUBBARD-WEST BECKER-EAST BECKER-WILKIN-
WEST OTTER TAIL-EAST OTTER TAIL-WADENA-GRANT-TOWNER-CAVALIER-
PEMBINA-BENSON-RAMSEY-EASTERN WALSH COUNTY-EDDY-NELSON-
GRAND FORKS-GRIGGS-STEELE-TRAILL-BARNES-CASS-RANSOM-SARGENT-
RICHLAND-WESTERN WALSH COUNTY-
303 PM CDT TUE AUG 16 2005

...SEVERE THUNDERSTORMS ARE EXPECTED ACROSS NORTHEASTERN NORTH DAKOTA
AND NORTHWEST MINNESOTA LATER TONIGHT...

...SEVERE THUNDERSTORMS CAN BE EXPECTED AGAIN WEDNESDAY AND
THURSDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN NORTH
DAKOTA...WEST CENTRAL AND NORTHWEST MINNESOTA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

ISOLATED THUNDERSTORMS ARE EXPECTED SOUTH OF A VALLEY CITY TO
FARGO TO PARK RAPIDS LINE THIS AFTERNOON NEAR A STATIONARY FRONT.
THESE STORMS ARE EXPECTED TO REMAIN BELOW SEVERE LIMITS.

THUNDERSTORMS ARE EXPECTED TO DEVELOP IN WESTERN NORTH DAKOTA
LATE THIS EVENING AND MOVE INTO EASTERN NORTH DAKOTA AFTER
MIDNIGHT...THEN INTO NORTHWEST MINNESOTA TOWARD DAYBREAK. THE MAIN
SEVERE THREATS WILL BE LARGE HAIL...WITH DAMAGING WINDS ALSO
POSSIBLE TOWARD DAYBREAK. A WARM FRONT WILL LIFT NORTHWARD
OVERNIGHT AIDING IN THUNDERSTORM DEVELOPMENT UNDER AN UNSTABLE
AIRMASS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A SLIGHT RISK OF SEVERE THUNDERSTORMS IS FORECAST FOR THE SOUTHERN
HALF OF THE RED RIVER VALLEY SOUTH OF A LINE FROM VALLEY CITY NORTH
DAKOTA TO WASKISH MINNESOTA. THE SEVERE WEATHER WILL BE MOST LIKELY
IN THE AFTERNOON AND EVENING AND WILL MOST LIKELY PRODUCE HAIL.

A SLIGHT RISK OF SEVERE THUNDERSTORMS IS FORECAST FOR AGAIN FOR THE
SOUTHERN HALF OF THE RED RIVER VALLEY AND IN THE SAME AREA FROM
VALLEY CITY NORTH DAKOTA TO WASKISH MINNESOTA. THE STORMS WOULD BE
MOST LIKELY FROM LATE MORNING INTO THE AFTERNOON WITH HAIL THE MOST
LIKELY THREAT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

JCA