Severe Thunderstorm Warning 32, NWS Marquette, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1030 AM EDT WED JUL 30 2003

FCST CONCERN THIS AFTN IS CONVECTION AND SVR POTENTIAL.

WV IMAGERY SHOWS MIDLEVEL LOW OVER SE MANITOBA DRIFTING TOWARD NWRN
MN. WARM CONVEYOR PCPN BAND EXTENDING FROM N OF LAKE SUPERIOR THRU
THE WRN U.P. INTO WI HAS BEEN SLOWLY EDGING E THIS MORNING.
RECENTLY...THIS PCPN HAS SHOWN A NOTICEABLE DIMINISHING TREND.
EXPECT TSTM DEVELOPMENT JUST AHEAD OF THIS BAND DURING AFTN HEATING
AND BEHIND IT WHERE CLOUDS ARE CLEARING OUT.

ETA AND RUC FCST SOUNDINGS MODIFIED FOR T/TD OF 76/63F YIELD CAPE
VALUES NEAR 2K J/KG. FORTUNATELY DEEP LAYER (0-6KM) SHEAR IS ONLY
10-20KT...LIMITING SIGNIFICANT STORM ORGANIZATION. HOWEVER...WET
BULB ZERO HEIGHTS OF 9-10KFT WILL MAKE SVR HAIL A THREAT...AND
FAVORABLE DECREASE OF THETA-E FROM SFC TO MIDLEVELS (NEAR OR
EXCEEDING 20K) WILL PROVIDE POTENTIAL FOR STRONG WIND GUSTS. AREAS
OVER THE CNTRL FCST AREA WHERE LAKE MICHIGAN LAKE BREEZE INTERSECTS
POTENTIAL OUTFLOW FROM WRN U.P. SHRA WILL NEED TO BE WATCHED.
ALTHOUGH ONGOING SHRA OVER WRN U.P. ARE DIMINISHING...NEW
DEVELOPMENT SHOULD TAKE OFF SOON WHERE CLOUDS ARE THIN.

GOING FCST IS GENERALLY IN GOOD SHAPE AND NO SIGNIFICANT CHANGES ARE
PLANNED IN UPDATE.

.MQT...NONE.

ROLFSON

MIZ001>007-009>014-084-085-311200-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MARQUETTE MI
700 AM EDT WED JUL 30 2003

...SLIGHT RISK THUNDERSTORMS THIS AFTERNOON AND EVENING WILL BECOME
SEVERE...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN AND CENTRAL UPPER
MICHIGAN.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS WILL SPREAD FROM WEST TO EAST TODAY...AND
BECOME MORE NUMEROUS TONIGHT. THERE IS A SLIGHT RISK THAT SOME OF
THE THUNDERSTORMS THIS AFTERNOON INTO EARLY EVENING MAY BECOMING
SEVERE AND CAUSE WIND GUSTS IN EXCESS OF 60 MPH AND HAIL AS LARGE AS
ONE INCH IN DIAMETER. THE GREATEST RISK OF SEVERE WEATHER WILL BE
WEST OF MUNISING AND ESCANABA. EXPECT SOME OF THUNDERSTORMS TO
PRODUCE LOCALLY HEAVY RAIN ACROSS MAINLY THE WEST HALF OF UPPER
MICHIGAN TODAY. THUNDERSTORMS TODAY WILL MOVE NORTHEAST AT 25 MPH.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THUNDERSTORMS ARE POSSIBLE THURSDAY THROUGH SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EARLY
EVENING.

ADDITIONAL WEATHER INFORMATION MAY BE OBTAINED AT THE FOLLOWING URL:

HTTP://WWW.CRH.NOAA.GOV/MQT (ALL LOWER CASE)

KC