Special Weather Statement, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
305 PM EDT THU MAR 15 2012

.SYNOPSIS...
ISSUED AT 305 PM EDT THU MAR 15 2012
SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS EVENING AS
WEAK LOW PRESSURE MOVES THROUGH. GENERALLY FAIR AND WARM WEATHER IS
EXPECTED THE NEXT SEVERAL DAYS BUT THERE WILL BE A CHANCE OF SHOWERS
AND THUNDERSTORMS SATURDAY INTO SATURDAY NIGHT.

&&

.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 305 PM EDT THU MAR 15 2012
WEATHER IMPACTS IN THE NEAR TERM INCLUDE POSSIBILITY OF ISOLATED TO
SCATTERED THUNDERSTORMS THIS EVENING AND DENSE FOG OVERNIGHT. MAIN
THREAT WITH THESE STORMS WILL BE LARGE HAIL AS STEEP LAPSE RATES
COMBINE TO PRODUCE UPDRAFTS WELL INTO THE MINUS 20C LAYER AT 20 KFT.

SOME HORIZONTAL ROLL CLOUD STREETS ARE NOTED ON THE VIS SATELLITE
IMAGERY THIS AFTERNOON AND SOME UPDRAFTS COULD GET GOING ALONG THESE
AS LAPS DATA SHOWS LARGE AREA OF MINUS 5 TO MINUS 7 SFC BASED LIFTED
INDICES AWAY FROM LAKE MICHIGAN. THE THREAT WILL PERSIST FOR INLAND
AREAS UNTIL INSTABILITY DECREASES AFTER SUNSET. AREAS NEAR THE LAKE
MICHIGAN COAST SHOULD SEE A STABLE LAYER PREVENT SHOWERS FROM
FORMING THERE.

LATER TONIGHT...DENSE FOG IS ALSO A CONCERN TONIGHT AS WINDS WILL GO
CALM AND LOW LEVELS REMAIN MOIST. WILL HAVE TO MONITOR FOR AREAS OF
DENSE FOG...ESPECIALLY ALONG LAKE MICHIGAN WHERE SFC DEW POINTS WILL
REMAIN WELL ABOVE WATER TEMPS.

.LONG TERM...(FRIDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 431 AM EDT THU MAR 15 2012
MAIN STORY CONTINUES TO BE THE UNSEASONABLY WARM WEATHER THAT IS
EXPECTED TO CONTINUE THROUGH THE LONG TERM.

UP AT 500MB/S...UPPER RIDGING BREAKS DOWN SLIGHTLY TO ALLOW A
SHORTWAVE TROUGH TO MOVE THROUGH SATURDAY NIGHT AND SUNDAY. THE
RIDGE TAKES OVER AGAIN EARLY NEXT WEEK...WITH THE GFS BEING
STRONGER/WARMER WITH IT. THE GFS HOLD FIRM AND KEEPS RIDGING IN
PLACE INTO MID WEEK...WHEREAS THE EUROPEAN BRING THE WESTERN TROUGH
EAST ACROSS THE PLAINS AND NUDGES IT CLOSE TO THE GREAT LAKES BY
WEDNESDAY EVENING. THE EUROPEAN SOLUTION WOULD BE A SLIGHTLY COOLER
SCENARIO BY MID NEXT WEEK.

BOTTOM LINE THOUGH IS EARLY SUMMER LIKE WEATHER WILL CONTINUE
THROUGH THE NEXT 7 DAYS...WITH TEMPERATURES 20 T0 30 DEGREES ABOVE
NORMALS FOR HIGHS. RECORD HIGHS WILL AT LEAST BE APPROACHED THE NEXT
7 DAYS IF NOT ECLIPSED. 850MB TEMPERATURES THROUGH THE PERIOD ARE
FORECAST TO BE BETWEEN +9 AND +13C WHICH SHOULD YIELD HIGH
TEMPERATURES IN THE 70S FOR HIGHS.

AT THIS POINT HAVE CHANCES FOR SCATTERED SHOWERS AND THUNDERSTORMS
FRIDAY NIGHT THROUGH SUNDAY AS THE WEAK 500MB SHORTWAVE TROUGH MOVES
THROUGH THE REGION. HAVE DRY WEATHER SUNDAY NIGHT THROUGH TUESDAY
NIGHT GIVEN LITTLE IN THE WAY OF A FORCING MECHANISM FOR STORMS.
BROAD SOUTHERLY FLOW IS EXPECTED THROUGHOUT THE PERIOD AT THE
SURFACE.

BEYOND THE 7 DAY PERIOD IT WILL BE INTERESTING TO WATCH THE
EVOLUTION OF A CUTOFF LOW THAT IS FORECAST TO MEANDER EASTWARD INTO
THE OHIO VALLEY LATE NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY MORNING)
ISSUED AT 141 PM EDT THU MAR 15 2012
ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND EVENING BUT
COVERAGE IS NOT EXPECTED TO BE MORE THAN SCATTERED ACROSS SOUTHERN
LOWER MICHIGAN FROM AZO TO JXN. MKG AND OTHER PLACES NEAR LAKE
MICHIGAN WILL SEE SOME SOME IFR STRATUS/FOG OFF LAKE MICHIGAN TODAY
AND TONIGHT.

&&

.MARINE...
ISSUED AT 305 PM EDT THU MAR 15 2012
FOG WILL BE THE MAIN WEATHER IMPACT ACROSS THE LAKE THE NEXT FEW
DAYS AS A WARM AND MOIST AIRMASS PERSISTS. VISIBILITIES SHOULD
REMAIN ABOVE A QUARTER MILE BUT COULD BE AS LOW AS A HALF MILE.

&&

.HYDROLOGY...
ISSUED AT 305 PM EDT THU MAR 15 2012
ONLY ISOLATED HEAVIER DOWNPOURS ARE POSSIBLE THROUGH THE WEEKEND
WHICH WILL HAVE LITTLE IMPACT ON RIVER LEVELS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM....DUKE
AVIATION...OSTUNO
MARINE...OSTUNO
HYDROLOGY...OSTUNO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
550 AM EDT THU MAR 15 2012

MIZ037>040-043>046-050>052-056>059-064>067-071>074-161000-
MASON-LAKE-OSCEOLA-CLARE-OCEANA-NEWAYGO-MECOSTA-ISABELLA-MUSKEGON-
MONTCALM-GRATIOT-OTTAWA-KENT-IONIA-CLINTON-ALLEGAN-BARRY-EATON-
INGHAM-VAN BUREN-KALAMAZOO-CALHOUN-JACKSON-
550 AM EDT THU MAR 15 2012

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

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS ARE EXPECTED TODAY...MOST NUMEROUS THIS MORNING
AROUND DAYBREAK AND AGAIN THIS AFTERNOON AND EVENING. SEVERE
STORMS ARE NOT EXPECTED...BUT THE STRONGER STORMS WILL BE CAPABLE
OF LOCALLY HEAVY RAIN...CLOUD TO GROUND LIGHTNING STRIKES AND HAIL
TO AROUND THREE QUARTERS OF AN INCH IN DIAMETER.

AREAS OF FOG ARE EXPECTED TONIGHT...SOME OF WHICH MAY BECOME DENSE
WITH VISIBILITIES BELOW A QUARTER OF A MILE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

SCATTERED THUNDERSTORMS ARE EXPECTED DURING THE FRIDAY NIGHT THROUGH
SUNDAY TIME FRAME. AT THIS POINT SEVERE STORMS ARE NOT EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

LMZ844>849-161000-
ST JOSEPH TO SOUTH HAVEN MI-SOUTH HAVEN TO HOLLAND MI-
HOLLAND TO GRAND HAVEN MI-GRAND HAVEN TO WHITEHALL MI-
WHITEHALL TO PENTWATER MI-PENTWATER TO MANISTEE MI-
550 AM EDT THU MAR 15 2012

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

.DAY ONE...TODAY AND TONIGHT

AREAS OF DENSE FOG ARE POSSIBLE OUT ON LAKE MICHIGAN TODAY AND
TONIGHT...ESPECIALLY SOUTH OF GRAND HAVEN.

SCATTERED THUNDERSTORMS ARE EXPECTED TODAY OUT ON LAKE
MICHIGAN...ESPECIALLY EARLY THIS MORNING AND AGAIN THIS AFTERNOON
AND EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

STORMS ARE POSSIBLE AGAIN FRIDAY NIGHT THROUGH SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

DUKE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
325 PM EDT THU MAR 15 2012

MIZ067-073-074-152030-
CALHOUN-INGHAM-JACKSON-
325 PM EDT THU MAR 15 2012

...SIGNIFICANT WEATHER ADVISORY...

AT 321 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
RAPIDLY DEVELOPING THUNDERSTORM 19 MILES NORTH OF JACKSON...MOVING
EAST AT 20 MPH. BY 345 PM EDT...OTHER THUNDERSTORMS SHOULD DEVELOP
EAST OF A LANSING TO BATTLE CREEK LINE AND ALSO MOVE EAST AT 20 MPH.

PEA SIZE HAIL...WINDS GREATER THAN 30 MPH...AND FREQUENT CLOUD TO
GROUND LIGHTNING...ARE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
  CLARK LAKE...         FITCHBURG...          CLARK LAKE...
  MUNITH...             WEBBERVILLE...        MICHIGAN CENTER...
  LEONI...              WATERLOO TWP...       NAPOLEON...
  GRASS LAKE...         STOCKBRIDGE...        BROOKLYN...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

STAY AWAY FROM HIGH OBJECTS OUTDOORS SUCH AS TREES. SEEK
SHELTER IN A STURDY STRUCTURE UNTIL STORMS HAVE PASSED.

&&

LAT...LON 4207 8414 4207 8529 4242 8500 4242 8460
      4277 8460 4278 8416 4245 8414 4239 8412
TIME...MOT...LOC 1923Z 281DEG 17KT 4251 8430

TJT