Severe Thunderstorm Warning 144, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
305 PM EDT THU SEP 22 2005

.SHORT TERM...
CONSIDERABLE CLOUD COVER CONTINUES IN LWR MI...AND WISCONSIN.
FRONTAL BOUNDARY AT 16Z APPEARS TO BE NEAR THE STRAITS OF MACKINAW
STRETCHING SOUTHWEST THROUGH GREEN BAY...AND NORTHEAST IOWA.
SCATTERED CONVECTION CONTINUES LATE THIS MORNING AND EXPECTED TO
REMAIN SCATTERED THROUGH THE NOON HOUR. A CLUSTER OF SHOWERS AND
THUNDERSTORMS WERE MOVING EAST THROUGH WEST CENTRAL LWR MI...THIS
WAS REMNANTS OF A MID MORNING MCS IN WISCONSIN.

SPC HOURLY MESO ANALYSIS PRESSURE CHANGE...INDICATES AT 16Z AN
INCREASING GRADIENT IN WESTERN IL...AND SE IOWA. UNDER SOUTHERLY SFC
FLOW...70 DEG DEWPTS WERE BEGIN ADVECTED INTO NE IL...AND EXPECT
THIS TO ENTER CENTRAL IN EARLY THIS AFTERNOON. 0-1 AND 0-3 KM
HELICITY VALUES WERE UPWARDS OF 200 TO 250. SO WITH A STRONG
SOUTHERLY BREEZE AHEAD OF THE FRONT...IF ANY INTENSE THUNDERSTORMS
DEVELOP THE POTENTIAL WILL BE AVAILABLE FOR ROTATION IN UPDRAFTS.
DEEP LYR SHEER REMAINS NEAR 50 TO 60 KNOTS...THUS THE MAIN THREATS
SHOULD BE WIND DAMAGE. PRECIP H2O VALUES IN THE WARM SECTOR WILL
REMAIN NEAR 1.6 INCHES...SO IT WOULD BE SUFFICE TO SAY TSTORMS COULD
PRODUCE BRIEF HEAVY DOWNPOURS.

THIS AFTN...850MB LOW LVL JET IS DIRECTED TOWARDS LWR MI AT 35KTS.
THIS WILL ONLY HELP WITH VERTICAL MOVEMENT. EXPECT COLD FRONT TO
SLOWLY WORK SOUTHEAST ACROSS CWA LATE THIS AFTERNOON AND EARLY
EVENING...AS MODELS INDICATE AROUND 00Z CLEARING GRR AND 03Z PUSHING
THROUGH CALHOUN...JACKSON...AND INGHAM COUNTIES. WINDS CONTINUE TO
SHIFT TO THE NORTH THIS EVENING. 850MB TEMPS FALL FRI TO A 9 TO 11
DEG C RANGE. THICKNESS VALUES OF 1370 DECAMETERS. COUPLED WITH
CONSIDERABLE SUBSIDENCE...AND SFC RIDGE DROPPING OVER THE TOP OF LWR
MI...TEMPS COULD STRUGGLE TO GET OUT OF THE 60S IN OUR NORTHERN
COUNTIES. UNDER A NE FLOW AT THE SFC...DOWN SLOPING WILL OCCUR AND
PUT THE WARMEST TEMPS ALONG THE SW CORNER. WOULD EXPECT SKIES TO
BEGIN MOSTLY SUNNY...THEN QUICKLY SEE CU DEVELOP AND POTENTIALLY
BECOME BROKEN BY 18Z.

FRIDAY EVENING THROUGH SATURDAY NIGHT...FRI WILL BE RATHER COOL
UNDER PARTLY CLOUDY SKIES. A FEW LOCATIONS IN INTERIOR NE COULD
FALL INTO THE UPPER 30S. SFC RIDGE SLIDES EAST INTO ONTARIO...WITH
INCREASING LOW LVL RH SAT MORNING. TROUGH BEGINS TO DIG ACROSS
INTERIOR OF WESTERN U.S. SFC WINDS BECOME SOUTHERLY SAT...AS
BOUNDARY LIFTS NORTH. LOW LVL JET BEGINS TO KICK IN LATE SAT
AFTERNOON. THICKNESS VALUES SUPPORT MAX TS WARMING BACK INTO THE
MID AND UPPER 70S SAT. GREATEST FGEN REMAINS WEST OF CWA...HOWEVER
GIVEN INCREASING LOW LVL JET THE POTENTIAL FOR CHC TSRA WILL BE
AVAILABLE.

.LONG TERM...
LATEST MEDIUM RANGE GUIDANCE CONTINUES TO SHOW WELL HAVE SHOWERS
AND STORMS IN ASSOCIATION WITH THE FRONT SUNDAY. IN FACT BASED ON
12Z GFS GUIDANCE A PRETTY GOOD SOAKING CERTAINLY APPEARS POSSIBLE
FOR OUR AREA. BEYOND THAT A HIGH PRESSURE RIDGE WILL BUILD IN AND
PRODUCE DRY WX MONDAY AND TUESDAY. ANOTHER LOW PRESSURE SYSTEM WILL
BRING US ANOTHER CHANCE OF SHOWERS AND STORMS WEDNESDAY. HOWEVER IT
APPEARS THE REMNANTS OF THE TROPICAL WILL NOT AFFECT OUR AREA AND
WILL LIKELY REMAIN CONFINED ACROSS THE WESTERN GULF COAST STATES
WHERE A TREMENDOUS AMOUNT OF RAINFALL IS LIKELY THIS WEEKEND AND
EARLY NEXT WEEK.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...SMALL CRAFT ADVISORY IN EFFECT
THROUGH TONIGHT.

&&

BEACHLER LAURENS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
105 PM EDT THU SEP 22 2005

LMZ844>849-MIZ037>040-043>046-050>052-056>059-064>067-071>074-231000-
ST JOSEPH TO SOUTH HAVEN-SOUTH HAVEN TO HOLLAND-
HOLLAND TO GRAND HAVEN-GRAND HAVEN TO WHITEHALL-
WHITEHALL TO PENTWATER-PENTWATER TO MANISTEE-MASON-LAKE-OSCEOLA-
CLARE-OCEANA-NEWAYGO-MECOSTA-ISABELLA-MUSKEGON-MONTCALM-GRATIOT-
OTTAWA-KENT-IONIA-CLINTON-ALLEGAN-BARRY-EATON-INGHAM-VAN BUREN-
KALAMAZOO-CALHOUN-JACKSON-
105 PM EDT THU SEP 22 2005

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS CONTINUE TO MOVE FROM WEST TO EAST ALONG THE
INTERSTATE 96 CORRIDOR AT 100 PM FROM MUSKEGON TO LANSING. A COLD
FRONT IS JUST NOW BEGINNING TO PRESS INTO WEST CENTRAL LOWER
MICHIGAN NEAR LUDINGTON AND MANISTEE...WHICH WILL MOVE SOUTHEAST
THROUGH THE SOUTHWEST QUARTER OF LOWER MICHIGAN THIS AFTERNOON AND
EVENING. THUNDERSTORMS SHOULD BEGIN TO MOVE AND DEVELOP INTO
SOUTHERN LOWER MICHIGAN TOWARD INTERSTATE 94 GIVEN BOUNDARIES SET UP
FROM PREVIOUS STORMS TO THE NORTH AND THE COLD FRONT DROPPING SOUTH.
CORRESPONDINGLY...THE STORM PREDICTION CENTER HAS PLACED AREAS SOUTH
OF A MUSKEGON TO ALMA LINE IN A SLIGHT RISK

THE MAIN THREATS WILL BE LARGE HAIL TO GOLF BALL SIZE... DAMAGING
WIND GUSTS TO 60 MPH AND LOCALLY HEAVY RAIN. AN ISOLATED TORNADO IS
NOT OUT OF THE QUESTION ALONG AND SOUTH OF INTERSTATE 96. THE BEST
TIME FOR SEVERE WEATHER WILL BE BETWEEN 200 PM AND 1000 PM THIS
AFTERNOON AND EVENING. THUNDERSTORM MOVEMENT WILL BE TO THE EAST
SOUTHEAST AT ABOUT 40 MPH.

3 TO 6 FOOT WAVES ARE EXPECTED ON LAKE MICHIGAN FROM HOLLAND NORTH
TODAY...AND OVER ALL OF THE NEARSHORE WATERS TONIGHT. THIS WILL POSE
A THREAT TO SMALL CRAFT AND CREATE AN INCREASED RISK OF RIP
CURRENTS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

WAVES ON LAKE MICHIGAN WILL GRADUALLY SUBSIDE ON FRIDAY AS WINDS
TURN TO THE EAST.

THE NEXT CHANCE OF THUNDERSTORMS WILL COME SATURDAY AFTERNOON AND
NIGHT AS A WARM FRONT LIFTS BACK NORTH THROUGH THE AREA. ANOTHER
COLD FRONT WILL COME THROUGH ON SUNDAY...WITH ADDITIONAL
THUNDERSTORMS EXPECTED. WAVES WILL LIKELY BUILD AGAIN ON LAKE
MICHIGAN.

HIGH PRESSURE WILL BRING COOL AND DRY CONDITIONS MONDAY AND
TUESDAY...AND PATCHY FROST IS NOT OUT OF THE QUESTION MONDAY NIGHT.

THE NEXT IN A SERIES OF FRONTS WILL ARRIVE WEDNESDAY...BRINGING YET
ANOTHER CHANCE OF THUNDERSTORMS TO SOUTHWEST MICHIGAN.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING.

MEADE DUKE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
138 PM EDT THU SEP 22 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0115 PM     HAIL             NORTON SHORES           43.16N 86.25W
09/22/2005  0.75 INCH        MUSKEGON           MI   LAW ENFORCEMENT

&&

BEACHLER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
244 PM EDT THU SEP 22 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0140 PM     TSTM WND DMG     ST. JOHNS               43.00N 84.56W
09/22/2005                   CLINTON            MI   LAW ENFORCEMENT

            NUMEROUS TREES AND POWER LINES DOWN IN THE CITY

&&

DUKE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
302 PM EDT THU SEP 22 2005

MIC005-015-025-037-045-065-067-075-077-081-139-159-230200-

THE NATIONAL WEATHER SERVICE HAS ISSUED SEVERE THUNDERSTORM WATCH
808 IN EFFECT UNTIL 10 PM EDT FOR THE FOLLOWING AREAS

IN MICHIGAN THIS WATCH INCLUDES 12 COUNTIES

IN SOUTH CENTRAL MICHIGAN

CALHOUN               CLINTON               EATON
INGHAM                IONIA                 JACKSON

IN SOUTHWEST MICHIGAN

ALLEGAN               BARRY                 KALAMAZOO
KENT                  OTTAWA                VAN BUREN

THIS INCLUDES THE CITIES OF...BATTLE CREEK...CHARLOTTE...
GRAND HAVEN...GRAND RAPIDS...HASTINGS...HOLLAND...IONIA...
JACKSON...KALAMAZOO...LANSING...SOUTH HAVEN AND ST. JOHNS.

LMZ844>846-867-868-230200-

THE NATIONAL WEATHER SERVICE HAS ISSUED SEVERE THUNDERSTORM WATCH
808 IN EFFECT UNTIL 10 PM EDT FOR THE FOLLOWING AREAS

THIS WATCH INCLUDES THE FOLLOWING ADJACENT COASTAL WATERS

ST JOSEPH TO SOUTH HAVEN
SOUTH HAVEN TO HOLLAND
HOLLAND TO GRAND HAVEN
OPEN WATERS FROM NEW BUFFALO TO HOLLAND
OPEN WATERS FROM HOLLAND TO WHITEHALL

DUKE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
346 PM EDT THU SEP 22 2005

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0343 PM     HAIL             GRAND HAVEN             43.06N 86.22W
09/22/2005  0.50 INCH        OTTAWA             MI   BROADCAST MEDIA

&&

GEO