Severe Thunderstorm Warning 34, NWS Marquette, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
1100 AM EST WED DEC 5 2001

MAIN FORECAST CONCERNS IN THE UPDATE ARE PCPN CHANCES FOR THIS
AFTERNOON... AND HIGH WIND CONCERNS TONIGHT. DON/T SEE MUCH REASON
TO MAKE MAJOR CHANGES TO THE GOING FORECAST... BUT WILL NEED TO MAKE
A FEW MINOR ADJUSTMENTS. LATEST SURFACE ANALYSIS PLACES THE LOW OVER
WESTERN MN... WITH THE WARM FRONT EXTENDING EAST ALONG THE SOUTHERN
EDGE OF THE CWFA AND THROUGH MENOMINEE COUNTY. THE WARM FRONT SHOULD
CONTINUE TO PUSH NORTH THROUGH THE AFTERNOON AS THE SURFACE LOW
RAPIDLY DEEPENS AND TRACKS NORTHEAST INTO ONTARIO BY EVENING.
ISENTROPIC LIFT IN THE 295-305K LAYER AHEAD OF THE WARM FRONT HAS
ALREADY MOVED NORTH OF THE CWFA... AND THE LATEST 88D IMAGERY SHOWS
THIS WAA PCPN MOVING AWAY TO THE NORTHEAST AT THIS TIME.

A FEW THUNDERSTORMS HAVE MANAGED TO DEVELOP FROM NEAR MINNEAPOLIS
NORTHEAST INTO NORTHWEST WI OVER THE PAST FEW HOURS. MSAS ANALYSES
INDICATE LIFTED INDICES OF 0 TO -2C ALONG THE AXIS WHERE THIS
CONVECTION IS DEVELOPING. IN ADDITION... MID-LEVEL LAPSE RATES HAVE
STEEPENED IN THAT AREA AHEAD OF THE H5 VORT LOBE WHICH IS
APPROACHING FROM THE WEST. IT WILL BE DIFFICULT FOR THE SURFACE
BASED INSTABILITY TO MAKE IT FAR INTO OUR CWFA THIS AFTERNOON WITH
TEMPERATURES LIKELY NOT WARMING AS DRAMATICALLY AS THEY HAVE TO OUR
SOUTH. HOWEVER... WITH THE MID LEVELS DRYING OUT FOR A SHORT TIME
THIS AFTERNOON... WE SHOULD SEE SOME BREAKS IN THE CLOUD COVER OVER
THE SOUTHERN COUNTIES AS THE AFTERNOON PROGRESSES. IN THE ABSENCE OF
SURFACE-BASED INSTABILITY... ELEVATED CONVECTIVE INSTABILITY IS
PRESENT THROUGH THE AFTERNOON HOURS PER 850-500MB DIFFERENTIAL
THETA-E PROGS FROM THE RUC AND 12Z ETA. WITH ALL OF THESE
CONSIDERATIONS IN MIND... AND ESPECIALLY WITH THE CLOSE PROXIMITY OF
ONGOING CONVECTION... WILL LIKELY THROW IN A MENTION OF THUNDER FOR
THE SOUTHERN COUNTIES FOR THIS AFTERNOON. OTHERWISE... WE SHOULD
PRIMARILY HAVE DRY WEATHER FOR A WHILE THIS AFTERNOON UNTIL THE
FORCING ALONG AND AHEAD OF THE COLD FRONT AND H5 TROUGH AXIS WORKS
THROUGH THE CWFA LATE THIS AFTERNOON AND THIS EVENING.

STRONG WINDS STILL LOOK LIKE A GOOD BET BEHIND THE COLD FRONT...
WITH SIGNIFICANT ISENTROPIC DOWNGLIDE/CAA AND PRESSURE RISES SLIDING
ACROSS THE CWFA FROM WEST TO EAST BETWEEN 00Z AND 06Z. WILL RETAIN
THE CURRENT WARNING FOR HOUGHTON... KEWEENAW AND NORTHERN ONTONAGON
COUNTIES... WITH NEAR ADVISORY WINDS MENTIONED ELSEWHERE.

.MQT...HIGH WIND WARNING TONIGHT MIZ001-MIZ003 AND NRN HALF
       OF MIZ002.
       STORM WARNING ON LAKE SUPERIOR THIS EVENING LSZ260.

TRH