Severe Thunderstorm Warning 3, NWS Grand Rapids, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
330 PM EST WED MAR 8 2000

...SHOWERS AND THUNDERSTORM LIKELY EARLY TONIGHT/ OCCASIONAL RAIN TO
SNOW THURSDAY...

QUITE A CHANGE ON THE WAY FOR TOMORROW.  LOOPS OF WATER VAPOR/IR/VIS
IMAGES SHOW JUST HOW STRONG THIS SYSTEM IS.  ONLY LIMITING FACTOR IS
THE LACK OF MID LEVEL MOISTURE.  GIVEN THE STRONG WINDS...60 KTS AT
850 AT 09/06Z FCST ON ETA FROM LAN TO JXN TO IND...WITH JET EXIT
REGION JUST TO SOUTH OF MICHIGAN... HAVE TO FAVOR AVN PCPN AREA OVER
REST OF MODELS.  THERE IS A GOOD DRY SURGE OVER THE MISSISSIPPI
RIVER AT 20Z AND A LINE OF TSTMS IS LIKELY TO FILL IN AS THIS AREA
MOVES EWD THIS EVENING.  BELIEVE THE LEADING EDGE ACTIVITY NEAR CHI
WILL DIPSATE BEFORE DOING MUCH.  SINCE BEST MID LEVEL RH OVER NRN
PART OF CWA TONIGHT HAVE 70 PCT POP THERE AND 60 PCT OVER SRN CWA.
SHOULD BE NOTED HELICITY FCST AROUND 400 AT GRR AT 03Z AND K INDEX
FCST ON SOUNDING 30 TO 35... TOTAL TOTALS IN MID 50S... 850 DWPTS
FCST FROM 6-8C.  ALL OF THIS WITH JET EXIT REGION AND MID LEVEL
LAPSE RATES 6.5 TO 7.5 C... SEEMS SOMETHING MORE THEN BKN MID CLDS
LIKELY TONIGHT. THIS WILL BE EAST OF CWA BY 300 AM SO PUT THAT IN
ZONES.

THURSDAY FINDS THE COLD AIR COMING IN WHILE THE 850/700 TROF HANDS
BACK AS 500 MB COLD POOL MOVES OVERHEAD.  THIS WILL RESULT IN
OCCASIONAL RAIN CHANGING TO SNOW NRN CWA AS RAPID COOLING AND STRONG
FRONTOGENESE OCCURS.  OVER SRN CWA MOISTURE NOT AS DEEP SO WENT WITH
RAIN SHOWERS MIXING WITH SNOW LATE. THAT WAS BASED ON 1000/850 ETA
THINNESS FIELD AND 925/850 TEMPS.  NOT TO MENTION FWC FCST PCPN TYPE.

DEEPER MOISTURE MOVES OUT AND CLDS NOT DEEP ENOUGH TO GET TO -10C
LEVEL BUT TROF STILL THERE OVER SRN LWR SO WILL FCST FLURRIES.  MAY
STILL HAVE FLURRIES BASED ON AVN FRIDAY BUT LEFT IT OUT FOR NOW.
MUCH COLDER THROUGH... ETA 1000/925 1000/850 925  AND 850 TMP FCST
COLDEST SINCE FEB 12.  SO IT WILL GET MUCH COLDER... BUT NOT AS COLD
AS NGM FCST... SO NEAR 20 FOR LOWS FRI NIGHT AND HIGHS MID 30S
FRIDAY.

ZONES BY 345 PM.

WDM

EXTENDED FORECAST
THE MEDIUM RANGE MODELS AREN/T EXACTLY CLOSING IN ON A SOLUTION IN
DAYS 3-5. ON SAT AM THE CANADIAN SHOWS A LOW THAT MOVED FROM THE SRN
PLAINS TO BE LOCATED IN WRN TN... WHILE THE AVN SHOWS THE LOW IN SRN
KY. THE ECMWF IS THE FARTHEST NORTH WITH THE LOW IN SE IN. THE MRF
IS THE FARTHEST EAST WITH THE LOW IN NE KY. WILL OPT FOR A SOLUTION
CLOSER TO THE AVN/ECMWF SINCE THE CANADIAN POSITION IS A LITTLE
FARTHER NE THAN IT/S PREVIOUS RUN. THE END RESULT IS A LOW THAT
MOVES FROM TX TO THE OH VALLEY. THE LOW MOVES NE TO NEW ENGLAND BY
SUN AND ANOTHER LOW IN THE NRN STREAM BEGINS TO MOVE SE TOWARD THE
GREAT LAKES AND ARRIVE BY MONDAY. THE MODELS ARE STILL QUITE A BIT
DIFFERENT THERMALLY SO WILL KEEP THE MENTION OF BOTH RAIN AND SNOW
ON SATURDAY. BY MONDAY THOUGH SUFFICIENT COLD AIR WILL BE IN PLACE
TO CREATE SNOW AS THE NRN STREAM WAVE APPROACHES.

.GRR...NONE.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS, MI
917 PM EST WED MAR 8 2000

TIME(EST)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0845 PM    SCOTTVILLE                MI   .75 INCH HAIL
03/08/00   MASON                          10 MINUTE DURATION

WDM

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS, MI
919 PM EST WED MAR 8 2000

TIME(EST)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0845 PM    SCOTTVILLE                MI   .75 INCH HAIL
03/08/00   MASON

920 PM    ROTHBURY                  MI   .75 INCH HAIL
03/08/00   OCEANA

930 PM    HART                      MI   .75 INCH HAIL
03/08/00   OCEANA

WDM