Severe Thunderstorm Warning 170, NWS Grand Forks, ND

FORECAST DISCUSSION FOR EASTERN NORTH DAKOTA AND NORTHWEST MINNESOTA
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS
300 AM CDT TUE AUG 8 2000

FCST CHALLENGE...SVR TSTM THREAT NW MN TDY.

ANALYSIS/MODEL GUIDANCE...SFC TROF EXTENDS SWD FM CLOSED LOW ALG
SASK/MAN BDR...THROUGH CNTRL ND (JUST WEST OF DVL-JMS) TO ERN NE.
VORT MAX IN NRN BRANCH FLOW AS SHOWN GOOD PERSISTANCE FM SRN ALTA
LAST NIGHT INTO SERN SASK THIS EVENING. RUC ANALYSIS SHOWS VORT HAS
SHEARED INTO TWO CNTRS NOW WITH SRN VORT DROPPING INTO NCNTL ND
CLOSE INTO THE LEFT-FRONT QUAD OF APCNG 70KT H3 JET. 00Z ETA
VERIFIES WELL WITH THIS FEATURE AND SEEMS TO BE HANDLING CONVECTION
IN NERN ND AND SRN MN WELL.

TDY...WILL STEER CLOSE TO 00Z ETA PACKAGE...06Z MESOETA IS LESS
ROBUST. AVN IS IN CLOSE AGREEMENT. CONVECTION IN NRN RRV HAS MOVED
OUT AHEAD OF THE SFC TROF AND HAS BEEN SOMEWHAT MOISTURE STARVED DUE
TO SRN MN MCS. HOWEVER ISOLD STRONG CELLS CONTINUE TO POPUP IN
MODERATELY UNSTABLE (CAPES 1500-2000) IN ERN ND. EXPECT ISOLD TO
WDLY SCT CONVECTION ACROSS ERN ND INTO THE RRV THROUGH EARLY MORNING
GENLY NORTH OF I-94. BY MIDDAY...LOW LVL MOISTURE FLUX RECOVERS INTO
NW MN AHEAD OF THE SFC TROF. EXPECT SCT CONVECTION TO FIRE ACROSS NW
MN BY MIDDAY...AS CONVECTIVE TEMPS FAIRLY LOW. FCST LIS DROP TO
MINUS 10 BJI-AXN AT 18Z WITH CAPES TO 3000+J/KG...SO WILL MENTION
SVR THREAT ALG AND EAST OF A FFM-BDE LINE. HAIL AND WIND BIGGEST
THREAT...ESPECIALLY WITH H3 JET DROPPING INTO AREA AND PUSHING 0-6KM
SHEARS TO >30M/S. ERN ND SHOULD SCT OUT LATE MORNING AS SFC TROF
SHIFTS INTO RRV. EXPECT SCT SKIES IN RRV THROUGH THE AFTERNOON. MOST
AREAS SHOULD SEE MAX TEMPS NEAR CLIMO NORMS...SIMILAR TO LAST COUPLE
DAYS AS AIRMASS HAS NOT CHANGED MUCH. LOW LVL MOIST AND WARM
ADVECTION AHEAD OF SFC TROF INTO NW MN SHOULD HELP PUMP TEMPS INTO
80 DEGREE RANGE MOST AREAS.

TNGT...MID LVL RHS DROP OFF RAPIDLY BEHIND THE SFC TROF AS IT EXITS
OUR ERN ZNS THIS EVENING. EXPECT SOME RESIDUAL LOW VFR CIGS IN LAKE
COUNTRY THROUGH THE EVENING...WITH CLEARING IN MOST AREAS BY
MIDNIGHT. WILL MENTION PATCHY FOG IN NW MN ZONES AS WINDS DROP OFF
LATE TONIGHT AND SKIES CLEAR. WIDESPREAD HEAVY PRECIP NOT EXPECTED
SO DENSE FOG NOT WORRY ATTM.

TMRW...WEAK H5 RIDGING BUILDS BACK INTO THE WRN DKTAS WED WITH SFC
HIGH PRES OVR ERN ND. EXPECT FAIR SKIES...WITH TEMPS HOLDING NEAR
SEASONAL NORMS.
;
.FGF...NONE.

GUST

MNZ001>009-013>017-022>024-027>032-040-NDZ006>008-014>016-024-
026>030-038-039-049-052>054-081400-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND
645 AM CDT TUE AUG 8 2000

...SEVERE THUNDERSTORMS ARE POSSIBLE IN NORTHWEST MINNESOTA TODAY...

SYNOPSIS...A SURFACE TROF WILL MOVE ACROSS THE RED RIVER VALLEY
THROUGH THE FORENOON AND MOIST SOUTHERLY FLOW WILL INCREASE ACROSS
NORTHWEST MINNESOTA AHEAD OF THIS TROF. MEANWHILE...AN UPPER LEVEL
DISTURBANCE WILL TRACK FROM CENTRAL NORTH DAKOTA INTO NORTHWEST
MINNESOTA AROUND MIDDAY. THIS COMBINATION WILL LEAD TO RAPID
THUNDERSTORM DEVELOPMENT THROUGH THE FORENOON INTO THE EARLY
AFTERNOON.

AREA OF CONCERN...ALONG AND EAST OF A FERGUS FALLS...RED LAKE FALLS
TO ROSEAU LINE.

TIME...BRIEFLY FROM 7 AM UNTIL 10 PM...AGAIN FROM NOON THROUGH 6 PM.

TYPE OF HAZARD...MAINLY LARGE HAIL THROUGH THE FORENOON...WITH LARGE
HAIL AND DAMAGIN]G WINDS IN THE AFTERNOON.

GUST

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PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE EASTERN NORTH DAKOTA/GRAND FORKS
653 AM CDT TUE AUG 08 2000

TIME(CDT)  .....CITY LOCATION..... STATE  ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0340 AM    7 WNW NORTHWOOD           ND   1 INCH HAIL
08/08/00   GRAND FORKS

0415 AM    2 E NORTHWOOD             ND   .75 INCH HAIL
08/08/00   GRAND FORKS

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