Severe Thunderstorm Warning 79, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1120 AM EDT THU JUL 17 2003

COLD FRONT CURRENTLY NEAR AN APN TO GRB LINE.  A FEW STORMS HAVE
DEVELOPED AND THEN DIMINISHED ALONG THIS FRONT THIS MORNING OVER
NORTHERN WI/MI AS THE INSTABILITY IS WEAK ATTM AND CIN VALUES ARE
RATHER HIGH.  THE FRONT WILL PROGRESS SOUTH INTO THE CWA DURING THE
AFTERNOON AND PASS THROUGH THE CWA BY EARLY EVENING.  SKIES ARE
MOSTLY SUNNY AHEAD OF THIS FRONT OVER MUCH OF THE CWA THIS MORNING.
THIS WILL ALLOW TEMPS TO REACH INTO THE LOWER 80S AHEAD OF THE
FRONT.  MOISTURE IS POOLING NEAR THE COLD FRONT WHERE DEWPOINTS ARE
IN THE MID AND UPPER 60S.  THESE HIGHER DEWPOINTS ARE INDICATED TO
ADVECT INTO THE CWA JUST AHEAD OF THE FRONT THIS AFTERNOON.  THIS
WILL PUSH CAPE VALUES TO AROUND 2000 J/KG THIS AFTERNOON.  WITH THIS
INSTABILITY EXPECT WELL SEE A BROKEN EAST TO WEST LINE OF STORMS
DEVELOP BY EARLY AFTERNOON OVER THE NORTHERN CWA WHICH SHOULD SLIDE
ACROSS THE REST OF THE CWA INTO THE EVENING.  WILL BUMP POPS INTO
THE LIKELY CATEGORY OVER THE ENTIRE CWA.  THERE IS STILL SOME
CONCERN FOR ISOLATED SEVERE THUNDERSTORMS AS MID LAYER DRYING IS
PRESENT... ALONG WITH 40 TO 45 KT WINDS IN THE MID LEVELS.  THERE IS
ALSO A DECENT AMOUNT OF SHEAR IN THE 0-4KM TO SUPPORT A FEW STRONGER
STORMS.

WILL UPDATE SKY CONDITIONS FOR SUNSHINE...MAINLY EARLY...AND ALSO
ADJUST TEMP FORECAST UP DUE TO THE ADDED SUNSHINE...ALONG WITH
BUMPING UP POPS.

.GRR...NONE.

MIZ037>040-043>046-050>052-056>059-064>067-071>074-181000-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1145 AM EDT THU JUL 17 2003

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

.DAY ONE...TODAY AND TONIGHT

A LINE OF STRONG THUNDERSTORMS IS EXPECTED TO DEVELOP EARLY THIS
AFTERNOON ALONG A COLD FRONT OVER CENTRAL LOWER MICHIGAN.  THIS LINE
WILL MOVE SOUTH INTO THE SOUTHERN MICHIGAN BY LATE AFTERNOON AS THE
FRONT DRIFTS SOUTH.  A FEW OF THE STRONGER STORMS COULD PRODUCE WIND
GUSTS TO 50 MPH ALONG WITH SMALL HAIL. DRIER AIR MOVING IN BEHIND
THE FRONT WILL END THE THREAT OF THUNDERSTORMS LATER THIS EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SCATTERED THUNDERSTORMS ARE EXPECTED LATE SUNDAY THROUGH EARLY
TUESDAY...AS A WEAK FRONT STALLS OVER LOWER MICHIGAN.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION SHOULD NOT BE NEEDED THIS AFTERNOON OR EVENING AS
ANY SEVERE WEATHER SHOULD BE RATHER ISOLATED.

JK