Severe Thunderstorm Warning 141, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1112 AM EDT SAT AUG 16 2003

AT 15Z THE COLD FRONT BISECTS LOWER MI FROM SAGINAW BAY TO JUST
SOUTH OF LDM.  INSTABILITY CONTINUES TO BUILD AHEAD OF THE FRONT
WHERE LI/S ARE PROGGED TO BE AROUND -5C AND CAPES BETWEEN 2-3K BY
MID AFTERNOON.  THE RUC SUPPORTS LOW LEVEL CONVERGENCE FROM BOTH THE
LAKE MICHIGAN AND LAKE HURON BREEZES...LEADING TO MORE ACTIVITY
INLAND THAN NEAR THE SHORES.  MID LAYER DRYING IS NOTED ON FORECAST
SOUNDINGS WITH A MID LEVEL JET STREAK OF 55-60KT COMING ACROSS.
THIS RISES THE POSSIBILITY OF A FEW SEVERE THUNDERSTORMS PRODUCING
STRONG WINDS...MAINLY OVER THE SOUTHERN 2/3 OF THE CWA.  ALTHOUGH A
FEW STORMS HAVE COME ACROSS THE NORTHERN PORTION OF THE CWA...AND
CONDITIONS HAVE STABILIZED THERE...WILL LEAVE POPS GOING THERE TOO
AS CONVECTIVE ACTIVITY MAY FORM OVER NORTHEAST WISCONSIN AND THEN
TRACK INTO CENTRAL LOWER THIS AFTERNOON.  THE FRONT IS FORECASTED TO
BE ALONG THE MI/IN BORDER BY 00Z SO THINKING NOW IS THAT MOST OF THE
STORMS WILL BE EXITING THE CWA BY 00Z.

.GRR...NONE.

JK

MIZ037>040-043>046-050>052-056>059-064>067-071>074-171045-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1152 AM EDT SAT AUG 16 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE SOUTHWEST QUARTER OF LOWER
MICHIGAN.

.DAY ONE...THIS AFTERNOON AND TONIGHT

A SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS MAINLY ALONG AND SOUTH
OF INTERSTATE 96 THIS AFTERNOON.  THE PRIMARY THREATS ARE DAMAGING
WINDS IN EXCESS OF 60 MPH AND HAIL UP TO AN INCH IN DIAMETER.  THE
STORMS THAT DO DEVELOP ARE FORECASTED TO TRACK SOUTHEAST AT 20 MPH.
BECAUSE OF THE VERY MOIST AIRMASS IN PLACE...LOCALLY HEAVY RAIN
COULD LEAD TO SOME POOR DRAINAGE FLOODING.  LIGHTNING COULD BE
FREQUENT WITH THE STRONGEST STORMS.

A COLD FRONT CURRENTLY OVER CENTRAL LOWER MICHIGAN IS FORECASTED TO
TRACK SOUTH THIS AFTERNOON...CROSSING SOUTHERN LOWER MICHIGAN BY
EVENING.  THE ATMOSPHERE WILL BECOME VERY UNSTABLE AHEAD OF THIS
FRONT.  SCATTERED THUNDERSTORMS SHOULD FORM ALONG THE FRONT THROUGH
THE AFTERNOON. THE ARRIVAL OF A STRONG UPPER LEVEL JET STREAM
DISTURBANCE AFTER 2 PM...COULD ENHANCE THE THUNDERSTORM ACTIVITY...
POSSIBLY LEADING TO A FEW SEVERE STORMS...AGAIN MAINLY SOUTH OF A
GRAND RAPIDS TO LANSING LINE.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON

MJS JK

MIZ043>045-050>052-056>059-064>067-071>074-170000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
225 PM EDT SAT AUG 16 2003

THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH
FOR PORTIONS OF THE SOUTHWEST QUARTER OF LOWER MICHIGAN EFFECTIVE
UNTIL 800 PM EDT SATURDAY EVENING. THIS WATCH INCLUDES THE FOLLOWING
COUNTIES

IN WEST CENTRAL MICHIGAN
     OCEANA...NEWAYGO AND MUSKEGON

IN CENTRAL MICHIGAN
     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.

MEADE