Severe Thunderstorm Warning 109, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
342 PM EDT WED JUN 23 2004

.SHORT TERM...
MAIN ISSUE IT THE THREAT FOR SEVERE WEATHER THIS EVENING. SECOND
ISSUE IS THE PRECIPITATION EVENT FOR THURSDAY AFTERNOON.  LITTLE
QUESTION ABOUT FRIDAY...MOSTLY SUNNY AND PLEASANT

FOR TONIGHT THERE IS A STRONG SHORTWAVE DROPPING SOUTHEAST FROM THE
DAKOTAS THIS AFTERNOON AND THE SURFACE WAVE OVER ERN IOWA/NW IL IS
WAITING FOR THAT WAVE. THAT MEANS THE FRONT WILL REMAIN STALLED OVER
CENTRAL LOWER MICHIGAN THIS EVENING TILL THAT SHORTWAVE MOVES IT
OUT. WITH THE AID OF A STRONG MID LEVEL JET...A 35 KNOT LOW LEVEL
JET NOSING INTO THE SOUTHWEST SECTIONS OF LOWER MICHIGAN BETWEEN 00Z
AND 06Z AND THE DPVA...SHOWERS AND SCT THUNDERSTORMS WILL BECOME
MORE WIDESPREAD ALONG AND NORTH OF INTERSTATE 96 THIS EVENING. THE
SHOWERS WILL BE MORE SCATTERED SOUTH OF INTERSTATE 96 SINCE THE
FRONT WILL NEVER GET THERE TONIGHT. DUE TO THE 60 TO 70 KNOTS OF
SHEAR BETWEEN 0 AND 6 KM... AND THE 6 TO 7C/KM LAPSE RATES
TONIGHT...ISOLATED LARGE HAIL (FREEZING LEVEL NEAR 10000 FT) NOT OUT
OF THE QUESTION BUT WHATEVER HAPPENS WILL BE ELEVATED BEING NORTH OF
THE SURFACE FRONT.

THAT MAIN UPPER WAVE MOVES ACROSS NRN LOWER MICHIGAN THURSDAY
AFTERNOON. THERE IS STRONG FG FORCING ASSOCIATED WITH THAT.
INSTABILITY IS ALMOST NIL ON THE ETA BUT STRONG OVER THE SE CWA ON
THE GFS DURING THE MORNING INTO EARLY AFTERNOON.  SINCE THE FRONT
WILL NOT HAVE CLEARED THE CWA TONIGHT...THE GFS IS LIKELY CLOSER TO
THE TRUTH. THUS HAVE SCT THUNDERSTORMS NEAR INTERSTATE 94 THURSDAY.
I ALSO HAVE 30 POP IN THE MORNING AND 50 POP IN THE AFTERNOON AND
EVENING SINCE THAT IS WHEN IT MORE THAN LIKELY WILL REALLY RAIN.

SKIES WILL CLEAR THURSDAY NIGHT...MOSTLY AFTER MIDNIGHT AS THAT WAVE
MOVES OUT AND THE DEEPER MOISTURE MOVES OUT.

FRIDAY WILL BE MOSTLY SUNNY AS RIDGING MOVES IN FROM THE SURFACE
THROUGH 850 MB.  WHILE THERE IS SHORTWAVE THE MOVES ACROSS THE NRN
CWA AROUND 18Z THE AIR WILL BE TO DRY OF MUCH OF ANYTHING.

.LONG TERM...
LATEST MEDIUM RANGE GUIDANCE CONTINUES TO INDICATE WELL HAVE VERY
TRANQUIL AND DRY WX THROUGH THE EXTENDED PERIOD, ACCOMPANIED BY A
GRADUAL MODERATING TREND OF TEMPS.  BY SATURDAY NIGHT A BROAD H5
TROUGH WILL STILL BE PARKED OVER THE EASTERN LAKES REGION AND
SEVERAL WEAK IMPULSES OF H5 ENERGY WILL PASS THROUGH. HOWEVER, RH
PROGS ARE NOT TOO IMPRESSIVE WITH MOISTURE SATURDAY NIGHT, AND WE
BELIEVE SUBSIDENCE UNDER THE WEAK HIGH PRESSURE RIDGE WILL INHIBIT
ANY SHOWERS FROM DEVELOPING.

THE SFC HIGH PRESSURE RIDGE WILL DOMINATE OUR WX EARLY TO MID NEXT
WEEK AND PRODUCE PARTLY TO MOSTLY CLEAR SKIES. THIS WILL BE
ACCOMPANIED BY A GRADUAL MODERATING TREND OF TEMPS AS THE H5 PATTERN
BECOMES MORE ZONAL AND 1000-500 MB HEIGHTS GRADUALLY RISE TO AROUND
582 DM BY LATE TUESDAY AND WEDNESDAY. THEREFORE TEMPS WILL RETURN TO
NEAR NORMAL LEVELS AND MAX TEMPS COULD REACH THE LOWER 80S BY
TUESDAY AND WEDNESDAY. DRY WX WILL PERSIST THROUGH WEDNESDAY.

&&

.GRR...NONE.

&&

WDM LAURENS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1110 AM EDT WED JUN 23 2004

MIZ037>040-043>046-050>052-056>059-064>067-071>074-241000-
ALLEGAN-BARRY-CALHOUN-CLARE-CLINTON-EATON-GRATIOT-INGHAM-IONIA-
ISABELLA-JACKSON-KALAMAZOO-KENT-LAKE-MASON-MECOSTA-MONTCALM-MUSKEGON-
NEWAYGO-OCEANA-OSCEOLA-OTTAWA-VAN BUREN-
1110 AM EDT WED JUN 23 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST LOWER
MICHIGAN.

.DAY ONE...THIS AFTERNOON AND TONIGHT

THUNDERSTORMS WILL LIKELY DEVELOP ACROSS THE SOUTHWEST QUARTER OF
LOWER MICHIGAN FROM MID AFTERNOON THROUGH THE EVENING. SOME STORMS
MAY BECOME SEVERE. THE STORM PREDICTION CENTER HAS PLACED THE ENTIRE
AREA IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS. THUNDERSTORMS WILL
BE POSSIBLE ACROSS THE AREA BETWEEN 200 PM AND 200 AM... WITH THE
BEST CHANCE FOR THUNDERSTORMS COMING DURING THE LATE AFTERNOON AND
EVENING HOURS. THE MAIN THREAT FROM STORMS WILL BE HIGH WINDS. SOME
OF THE STRONGEST STORMS MAY CONTAIN WINDS TO NEAR 60 MPH.
THUNDERSTORM MOVEMENT WILL BE TO THE EAST AT 40 MPH. ISOLATED
TORNADOES CANNOT BE RULED OUT EITHER LATE THIS AFTERNOON AND
EVENING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THUNDERSTORMS ARE POSSIBLE AGAIN ON THURSDAY. STORMS SOUTH OF
INTERSTATE 96 MAY REACH SEVERE LEVELS. HIGH WINDS AGAIN APPEAR
TO BE THE MAIN THREAT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED BOTH TODAY AND THURSDAY.

LAURENS

MIZ043>046-050>052-056>059-064>067-071>074-240400-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
606 PM EDT WED JUN 23 2004

THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR PORTIONS OF THE SOUTHWEST QUARTER OF LOWER MICHIGAN EFFECTIVE
UNTIL MIDNIGHT EDT THURSDAY MORNING. THIS WATCH INCLUDES THE
FOLLOWING COUNTIES

IN WEST CENTRAL MICHIGAN
     OCEANA...NEWAYGO AND MUSKEGON

IN CENTRAL MICHIGAN
     ISABELLA...MECOSTA...MONTCALM AND GRATIOT

IN SOUTHWEST MICHIGAN
     KENT...ALLEGAN...BARRY...KALAMAZOO...VAN BUREN AND OTTAWA

IN SOUTH CENTRAL MICHIGAN
     IONIA...CLINTON...INGHAM...EATON...JACKSON AND CALHOUN

THIS WATCH INCLUDES THE ADJOINING COASTAL WATERS OF AFFECTED
LAKESHORE COUNTIES.

A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR
THE DEVELOPMENT OF SEVERE THUNDERSTORMS IN AND NEAR THE WATCH AREA.
REMEMBER...SEVERE THUNDERSTORMS PRODUCE WIND GUSTS IN EXCESS OF 58
MPH AND/OR HAIL THREE-QUARTERS OF AN INCH IN DIAMETER OR GREATER. IF
YOU LIVE IN OR NEAR THE WATCH AREA YOU SHOULD REMAIN ALERT TO RAPIDLY
CHANGING WEATHER CONDITIONS. STAY TUNED TO NOAA WEATHER RADIO OR THE
LOCAL NEWS OUTLETS FOR THE LATEST UPDATES AND POSSIBLE WARNINGS.

MJS