Severe Thunderstorm Warning 29, NWS Grand Forks, ND

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
245 PM CDT SAT JUN 21 2003

MAIN FORECAST CHALLENGE REMAINS CONVECTIVE POTENTIAL THROUGHOUT THE
EARLY PERIODS. MODELS IN VERY GOOD AGREEMENT WITH LARGE SCALE
FEATURES AND DIFFER MOST WITH USUAL THERMAL FIELDS AND CONVECTIVE
QPF PLACEMENT. WILL CONTINUE TO FOLLOW A MODEL BLEND IN THE GRIDS.

WILL FIRST EXTEND WIND ADVISORY INTO THE EARLY EVENING. OTHERWISE...
WILL BE WATCHING FOR CONVECTION TO FIRE LATE THIS AFTERNOON/EARLY
EVENING. COLD FRONT NOW OVER WESTERN ND WITH DEW POINTS IN THE
LOW-MID 60S ALONG/AHEAD OF THE FRONT. MSAS SHOWS LIS OF -7 WEST OF
KBIS ALONG WITH GOOD MOISTURE CONVERGENCE. ETA STILL PEGGING
PORTIONS OF THE FA WITH CAPE OF 1500-2200 J/KG BY 00Z SUN. AS
MENTIONED IN PRIOR DISCUSSION...CONVECTIVE TEMPS PRETTY HIGH
INITIALLY (UPPER 80S). SO AS BETTER DYNAMICS AND CONVERGENCE ALONG
THE COLD FRONT COME INTO PLAY LATE THIS AFTERNOON/EVENING...STORMS
ARE EXPECTED TO RAPIDLY INTENSIFY AND SPREAD ENE. INHERITED ZONES
HAVE LONG BEEN ADVERTISING THE SEVERE/HEAVY RAIN POTENTIAL TONIGHT.
MAIN THREATS LOOK TO REMAIN LARGE HAIL AND DAMAGING WINDS. FRONTAL
BOUNDARY WILL STALL OVER EASTERN ND BY 12Z SUN...SO STILL EXPECT
TEMPS TO HOLD UP PRETTY HIGH TONIGHT WITH BEST FALL POTENTIAL IN THE
WESTERN FA. THE GUSTY WINDS SHOULD TAPER OFF AGAIN THIS EVENING
(AWAY FROM ANY STORMS).

WILL LIKELY AGAIN BE SOME LINGERING CONVECTIVE CLOUD DEBRIS LEFT
OVER SUN MORNING. WILL NOT BE TOO CUTE WITH TIMING ON THE THUNDER
REDEVELOPMENT. WITH A POTENTIAL FOR SOME LINGERING SHOWER/STORMS
EARLY AND DEVELOPMENT AGAIN IN THE AFTERNOON...WILL JUST LEAVE A
BROADBRUSHED CHANCE IN THE GRIDS. HOW FAST THE FRONTAL BOUNDARY
MOVES AND WHERE IT SETS UP ON SUN WITH HAVE A BIG AFFECT ON TEMPS.
WILL GO A BIT COOLER...ESPECIALLY ACROSS THE NORTH. SPC HAS EXPANDED
THE MODERATE RISK AREA A BIT FURTHER NORTH SUNDAY AND ALSO BACKED
THE SLIGHT RISK AREA BACK INTO THE KDVL REGION. UPPER JET DYNAMICS A
BIT MORE IMPRESSIVE AS ARE THE 500 MB WINDS. GOOD MOISTURE FEED ALSO
REMAINS IN PLACE. WILL AGAIN GO WITH SEVERE/HEAVY RAIN WORDING LATE
SUN AFTERNOON/SUN NIGHT IN THE GRIDS. MODELS DIFFER A BIT ON MON
STORM SOLUTIONS...BUT WITH BOUNDARY AND SPC DAY 3 SLIGHT RISK AREA
CLOSE BY...WILL ADD IN A THUNDER CHANCE ACROSS SOUTHERN ZONES. WILL
PUSH BACK THE BRIEF DRY BREAK INTO MON NIGHT AND KEEP THUNDER CHANCE
TUE.

.EXTENDED...MRF SHOWS LONG WAVE TROF EXTENDING FROM IDAHO PANHANDLE
TO THE FOUR CORNERS WITH RRV STILL IN SOUTHWESTERLY FLOW ALOFT.
HOWEVER...SFC HIGH SETTLES OVER THE BLACK HILLS OF SOUTH DAKOTA
LEAVING US WITH FEW CLOUDS AND A WARM DAY.  SFC LOW EJECTED FROM
FOUR CORNERS STARTS TO AFFECT RRV BY MID TUESDAY WITH WRAP-AROUND
RAIN TUESDAY NIGHT.  RRV CLEARS AS UPPER AIR TROF PASSES TO EAST AND
NORTHWESTERLY FLOW ALOFT COMES INTO PLAY.  MRF NOW SHOWS NEXT CHANCE
FOR RAIN ON THURSDAY VICE FRIDAY AS BEFORE...BUT SINCE FLIP-FLOP
BETWEEN DAY 6 AND DAY 7 IS SUSPECT...WE WILL NOT CHANGE IFPS GRIDS
AT THIS TIME.

.FGF...WIND ADVISORY FOR THE RED RIVER VALLEY UNTIL 9 PM CDT.

GODON/LUKES

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-211400-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
547 AM CDT SAT JUN 21 2003

...SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS EASTERN NORTH
DAKOTA...NORTHWEST AND WEST CENTRAL MINNESOTA THIS AFTERNOON THROUGH
SUNDAY NIGHT...

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

.DAY ONE...TODAY AND TONIGHT
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS ALL OF EASTERN
NORTH DAKOTA...NORTHWEST AND WEST CENTRAL MINNESOTA THIS AFTERNOON
THROUGH SUNDAY. SEVERE THUNDERSTORMS MAY DEVELOP BY 3 PM THIS
AFTERNOON IN EASTERN NORTH DAKOTA...THEN MOVE EAST INTO MINNESOTA
THROUGH THE OVERNIGHT HOURS. THE MAIN THREAT WILL BE LARGE HAIL AND
DAMAGING WINDS...ALTHOUGH THERE IS THE CHANCE FOR A FEW ISOLATED
TORNADOES LATE THIS AFTERNOON AND EVENING ACROSS EASTERN NORTH
DAKOTA AND EXTREME NORTHWEST AND WEST CENTRAL MINNESOTA. IN ADDITION
...SOME THUNDERSTORMS MAY PRODUCE LOCALIZED HEAVY RAINFALL.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS EASTERN NORTH
DAKOTA AND NORTHWEST MINNESOTA ON SUNDAY. THERE IS A MODERATE RISK
OF SEVERE THUNDERSTORMS ON SUNDAY ALONG AND SOUTH OF A LIDGERWOOD TO
WAHPETON TO WADENA LINE. THE MAIN THREAT WILL BE LARGE HAIL AND
DAMAGING WIND...WITH ISOLATED TORNADOES IN THE MODERATE RISK AREA.
THUNDERSTORMS SHOULD DIMINISH SUNDAY MORNING...BUT ONCE AGAIN
DEVELOP EARLY SUNDAY AFTERNOON ACROSS THE ENTIRE REGION AND PERSIST
THROUGH SUNDAY NIGHT. HEAVY RAIN IS ONCE AGAIN POSSIBLE...WHICH MAY
CAUSE LOCALIZED FLOODING...ESPECIALLY TO AREAS RECEIVING HEAVY RAIN
ON SATURDAY AND SATURDAY NIGHT.

THERE IS THE CHANCE FOR THUNDERSTORMS ACROSS THE REGION MONDAY NIGHT
AND TUESDAY...THEN AGAIN ON FRIDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL LIKELY BE NEEDED LATER THIS AFTERNOON
THROUGH SUNDAY NIGHT ACROSS THE AREA.

KELLENBENZ