Flash Flood and Hail in Minnesota, September 25, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND FORKS ND
347 AM CDT THU SEP 25 2008

.SHORT TERM...CHALLENGE WILL BE TEMPERATURES AND PRECIP CHANCES.
THERE IS THE POTENTIAL FOR SOME SEVERE STORMS WITHIN THE NEXT
COUPLE DAYS. 00Z MODELS IN GENERAL AGREEMENT AND WILL USE BLEND.

AS OF 09Z...RADARS BEGINNING TO SHOW RETURNS ACROSS E SD INTO OUR
EXTREME S FA. THIS OCCURRING ON LEADING EDGE OF 35-40KT 850MB JET
(IMPLIED STRONG WARM AIR ADVECTION). 850MB MOISTURE ADVECTION
FAIRLY STRONG...AND EXPECT ATMOSPHERE TO QUICKLY DESTABILIZE
ACROSS THE S FA BY 12Z. THERE WILL BE A FEW HOURS EARLY THIS
MORNING WHERE THE POTENTIAL FOR A COUPLE SEVERE HAIL REPORTS WILL
EXIST CONSIDERING DEEP LAYER SHEAR AROUND 40KTS. OVERALL SEVERE
THREAT SHOULD BE LIMITED CONSIDERING STRONGEST INSTABILITY IS
LAGGING STRONGEST FORCING.

STRONGEST FORCING (ISENTROPIC LIFT...WARM AIR ADVECTION) SHIFTS NE
THROUGH THE MORNING CLIPPING THE S/SE FA. WILL TRIM POPS ACROSS
THE NE FA WITH ALL MODELS INDICATING DRY THIS AREA. SOUTHERLY
RETURN FLOW...WEAK WARM AIR ADVECTION CONTINUES THROUGH THE DAY
TODAY...AND WITH SUFFICIENT MIXING EXPECT MAX TEMPS WELL INTO THE
70S NEAR 80F.

LOW-LEVEL MOISTURE CONTINUES TO INCREASE INTO THUR NIGHT...AND
MODELS INDICATING 850MB CAPE NEAR 2000 J/KG AHEAD OF MID-LEVEL
TROUGH. INCREASING 850MB WINDS IN CONJUNCTION WITH NEAR ZERO
850MB CIN ACROSS THE E FA LEADS TO ADDING ISOLD THUNDER WHERE CAP
IS WEAKEST. COULD BE A FEW SEVERE HAIL REPORTS WITH DEEP LAYER
SHEAR NEAR 40KTS AND MODERATE INSTABILITY. OTHERWISE WILL BE A
MILD NIGHT WITH FA UNDERNEATH THERMAL RIDGE.

COLD FRONT CROSSES THE FA ON FRI. KEPT IDEA OF LOW END POPS
THROUGH THE MORNING WITH FAIRLY STRONG CAPPING LIKELY. HIGHER POPS
ALONG AND AHEAD OF EXPECTED FRONTAL POSITION WHEN MID-LEVEL
COOLING ARRIVES TO WEAKEN THE CAP. SWODY2 SHOWS SLIGHT RISK FOR
SEVERE STORMS CONSIDERING MODERATE INSTABILITY AND STRONG DEEP
LAYER SHEAR AS WELL AS DECENT LOW LEVEL CONVERGENCE.

HIGH PRESSURE MOVES INTO THE REGION FOR SAT WITH DRY WX AND
COOLER TEMPS EXPECTED.

.LONG TERM...LOWERED TEMPS A BIT SUN INTO MON WITH MODELS TRENDING
COOLER. OTHERWISE NO CHANGES.

&&

.AVIATION...VFR CONDITIONS EXPECTED. MAIN CHALLENGE WILL BE
THUNDERSTORM POTENTIAL...WITH KFAR (POSSIBLY KBJI) THE MOST LIKELY
LOCATION TO SEE ANY THUNDER. REMAINDER OF TAF SITES SHOULD BE
NORTH OF ACTIVITY THROUGH THE DAY.

&&

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

TG

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND FORKS ND
115 PM CDT WED SEP 24 2008

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-251815-
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-
115 PM CDT WED SEP 24 2008

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED TO LIFT NORTHWARD INTO THE
REGION AFTER MIDNIGHT AS MOIST UNSTABLE AIR SPREADS NORTH MAINLY
INTO SOUTHERN PARTS OF THE REGION.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE EAST OF THE RED RIVER
ON THURSDAY. THE NEXT CHANCE FOR MORE ORGANIZED THUNDERSTORMS WILL
BE FRIDAY AFTERNOON AND EVENING WITH THE PASSAGE OF A COLD FRONT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

VOELKER