Hail in North Dakota, June 13, 2001

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
220 PM CDT WED JUN 13 2001

FORECAST CHALLENGE WILL BE CONVECTIVE THREAT THROUGHOUT

.OVERVIEW...
LATEST ANALYSIS SHOWS MAIN SFC LOW OVER SOUTHEAST SD...WITH INVERTED
TROUGH STRETCHING NORTH/NORTHEAST INTO EASTERN FA. DEWPOINTS ARE
AROUND 60 ALONG TROUGH...AND HIGHER TO SOUTH AND EAST. MORE STABLE
AND DRIER AIR AT THE SFC IS IN PLACE TO THE WEST OF INVERTED TROUGH
WITH DEWPOINTS IN THE LOW AND MIDDLE 50S. MODELS ARE HAVING A TOUGH
TIME RESOLVING DETAILS WITH THIS COMPLEX UPPER LOW EJECTING OUT OF
ROCKIES. HAVE LEANED TOWARDS THE AVN SFC PLACEMENT OF SYSTEM...BUT
TRENDED TOWARDS ETA MOISTURE FIELDS.

.SHORT TERM...
WEAK NVA AND ASSOCIATED Q VECTOR DIVERGENCE WILL KEEP THE NORTHERN
2/3 OF THE FA MOSTLY DRY OVERNIGHT...WITH JUST SOME SCATTERED
SHOWERS. IN THE SOUTHERN 1/3 OF THE AREA...CLOSER TO THE INVERTED
TROUGH AND DEEPER MOISTURE...I EXPECT MORE IN THE WAY OF SCATTERED
THUNDERSTORMS. LI/S APPROACH -3C WITH CAPES NEAR 1000 J/KG HERE BY
00Z COUPLED WITH 55KT SPEED MAX AT 500MB. THIS COUPLED WITH MODEST
SFC CONVERGENCE SHOULD AID THUNDERSTORMS. WITH PRECIPITABLE WATERS
NEAR 1.50 INCHES...AND 850MB JET INCREASING TO NEAR 45KT BY
00Z...ANY THUNDERSTORMS WHICH DEVELOP SHOULD PRODUCE HEAVY RAIN.
WITH UPPER FLOW PARALLELING INVERTED TROUGH NEAR SOUTHERN FA...WILL
ISSUE FLASH FLOOD WATCH FOR EXTREME SOUTHERN FA TONIGHT.

.LONG TERM...
ON THURSDAY...UPPER LOW BEGINS TO EJECT NORTHEAST...WITH SFC LOW
MOVING INTO SOUTHEAST SD BY 00Z FRI. AHEAD OF FEATURE 850MB MOISTURE
CONVERGENCE AND JET INCREASE. IN ADDITION...DEFORMATION NEAR 500MB
AND LARGE SCALE LIFT PER 850-500MB Q VECTOR CONVERGENCE INCREASE
AROUND 00Z. THIS SHOULD PROMOTE SHOWER AND THUNDERSTORM DEVELOPMENT
DURING THE AFTERNOON. LI/S APPROACH -4C WITH 1500J/KG CAPES BY
AFTERNOON IN SOUTHEAST...SO MAY EVEN SEE A FEW SEVERE STORMS WITH
GOOD 0-6KM SHEAR. ON THURSDAY NIGHT...DEFORMATION RAIN SHOULD
DEVELOP...AND MAY EVEN BE HEAVY AT TIMES WITH QPF AMOUNTS NEAR 1
INCH. IN ADDITION...LEFT EXIT REGION OF 300MB 120KT COUPLED JET
STRUCTURE WILL ALSO AID LARGE SCALE LIFT...WITH PRECIPITABLE WATER/S
NEAR 1.50 INCHES. WILL ISSUE SPS TO HIGHTLIGHT THU AFTERNOON INTO
EARLY FRIDAY HEAVY RAIN POTENTIAL FOR THUNDERSTORMS IN SOUTHERN
FA...AND DEFORMATION RAIN FURTHER NORTH. LOW SLOWLY LIFTS NORTHEAST
INTO ONTARIO FRIDAY...AND A DRIER AIR WILL FILTER IN ALONG WITH SOME
SUNNY BREAKS BY AFTERNOON. WILL BRING DECREASING CLOUDS INTO WEST ON
FRIDAY.

.EXTENDED...LONG RANGE MODELS IN GOOD AGREEMENT THRU THE PD WITH ALL
ADVERTISING CHANGE TO MORE ZONAL FLOW OVER THE REGION. ONE WEAK SHRT
WV PASSES THRU THE REGION LATE IN THE WEEK...BUT WITH ZONAL FLOW
THIS FEATURE SHOULD BE OUT OF THE AREA PRIOR TO START OF EXTENDED.
SYS DIVING INTO THE PAC NW ON MON TO SHIFT 5H FLOW A BIT MORE SW
WITH UNSETTLED WX RETURNING TO THE REGION AFTER A DRY WEEKEND WITH
BEST CHC FOR PCPN MON NIGHT/TUE MORNING. PAC NW SYS SHEARS OUT IN
ZONAL FLOW AND MOVES THRU ON WED BRINGING A CHC FOR SHOWERS THEN.
WARMEST READINGS EXPECTED ON MON WITH REMAINDER OF EXTENDED SEASONAL
OR SLIGHTLY BLO NORMAL.

.FGF...FLASH FLOOD WATCH TONIGHT FOR
RANSOM...SARGENT...RICHLAND...WILKIN...GRANT...OTTERTAIL...HUBBARD
AND WADENA.

KELLENBENZ/TURNER

MNZ002-003-022>024-027>032-040-NDZ028>030-038-039-049-052-053-132255-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
401 PM CDT WED JUN 13 2001

...SEVERE THUNDERSTORMS ARE POSSIBLE TONIGHT OVER SOUTHEAST NORTH
DAKOTA AND WEST CENTRAL MINNESOTA...

SYNOPSIS...LOW PRESSURE OVER NORTHEAST SOUTH DAKOTA WITH ASSOCIATED
WARM FRONT RUNNING UP INTO WEST CENTRAL MINNESOTA. THIS IS CAUSING
A WARM...MOIST AND UNSTABLE AIRMASS TO SURGE NORTHWARD INTO THE
REGION. THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE NEXT FEW HOURS
AND BECOME SEVERE.

AREA OF CONCERN...A MODERATE RISK OF SEVERE WEATHER IS FORECAST
SOUTH AND EAST OF A LINE FROM FORMAN UP TO FARGO AND EAST TO PARK
RAPIDS. A SLIGHT RISK OF SEVERE WEATHER IS FORECAST SOUTH OF A LINE
FROM MAYVILLE TO BEMIDJI.

TIME...430 PM TO 11 PM.

TYPE OF HAZARD...MAIN THREATS WILL BE TORNADOES AND LARGE HAIL ALONG
AND NORTH OF THE WARM FRONT.

DONAVON