Severe Thunderstorm Warning 59, NWS Detroit, MI

SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
453 AM EDT SUN JUL 28 2002

CURRENTLY CHASING THE CONVECTION ALONG THE SURGE OF DEEP HIGH
THETA-E AIR OUT OF THE FORECAST AREA.  ADDITIONAL ACTIVITY ACROSS
CENTRAL LOWER CONTINUES ITS TREK NORTHEAST.  WILL CARRY NUMEROUS
WORDING ACROSS THE NORTH TO COVER CURRENT ACTIVITY.  OTHERWISE...
SKIES ARE CLEARING ACROSS THE SOUTH SO WILL HAVE MOSTLY SUNNY
CONDITIONS FOR THE MORNING, BEFORE THE CU FIELD DEVELOPS WITH THE
HEATING OF THE DAY.  SPEAKING OF THE HEAT OF THE DAY, WITH HIGHS
EXPECTED TO BE AROUND 90, IF NOT A COUPLE DEGREES HIGHER, AND
DEWPOINTS IN THE 70-75F RANGE- HEAT INDICES WILL CLIMB TO AROUND
100.  WILL HOLD ON A HEAT ADVISORY FOR NOW, BUT IF THE AREA SEES A
LONGER PERIOD OF SUN THAN CURRENTLY EXPECTED, ADVISORY CRITERIA IS
NOT OUT OF THE QUESTION.

SYNOPTIC-SCALE BOUNDARY IS PROGGED TO HANG AROUND SOUTHERN LOWER
MICHIGAN THROUGH THE DAY AS ANOTHER SURGE OF HIGH THETA-E AIR AT 850
AND 700MB MOVES IN FROM THE SOUTHWEST IN ADVANCE OF A WEAK
SHORTWAVE.  THE SOUTHERN THIRD OF THE LOWER PENINSULA WILL BE UNDER
THE INFLUENCE OF THE DIRECT THERMAL CIRCULATION SUPPORTED BY THE
RIGHT ENTRANCE REGION TO A 300MB SPEED MAX TRAVERSING THE CENTRAL
LAKES REGION THIS AFTERNOON.  THIS IN COMBINATION WITH THE
QUASI-STATIONARY SYNOPTIC-SCALE BOUNDARY AND PRE-EXISTING OUTFLOW
BOUNDARIES FROM THIS MORNING/S CONVECTION SHOULD BE ENOUGH TO AID
ADDITIONAL CONVECTIVE INITIATION WITH THE HEAT OF THE DAY.  ETA
HOURLY SOUNDINGS INDICATE THAT CAPES WILL CLIMB INTO THE 2500 J/KG
RANGE ACROSS THE CWFA WITH THE MOIST LAYER EXTENDING TO 700MB AND
SUBSTANTIAL DRYING ABOVE THAT.  TEMPS AT 700MB SHOULD STAY BELOW
+10C KEEPING THE REGION NORTH OF THE EDGE OF THE CAPPING INVERSION
THAT SETUP ACROSS THE MID-MISSISSIPPI VALLEY YESTERDAY.  THE DRY AIR
ALOFT IN COMBINATION WITH THE INCREASING MOMENTUM IN THE PROFILE
COULD SUPPORT A FEW SEVERE CELLS ONCE AGAIN TODAY, WITH WIND BEING
THE PRIMARY THREAT, AS THE FREEZING LEVEL WILL STILL BE AROUND
15KFT.  THE HODOGRAPH IS REASONABLY STRAIGHT WITH MODEST SHEAR IN
THE LOWEST 2KM, LENDING TO SOME ORGANIZATION BUT MORE OF THE SHORT
LINEAR VARIETY.

WILL ALSO HAVE TO KEEP A WATCHFUL EYE UPSTREAM AS ADDITIONAL
ORGANIZED CONVECTION IS EXPECTED ACROSS IOWA AND MINNESOTA DURING
THE EVENING, WHICH MAY MOVE INTO THE SOUTHERN LAKES REGION
OVERNIGHT.  INSTABILITY ACROSS THE REGION WOULD CERTAIN SUPPORT
CONTINUED NOCTURNAL DEVELOPMENT.  SO, WITH CONTINUE THE CHANCE FOR
SHOWERS AND STORMS TONIGHT.

THE BEST CHANCE WILL STILL COME MONDAY, WHEN THE STRONGER SHORTWAVE
OVER THE ROCKIES ARRIVES, WITH THE ASSOCIATED SURFACE COOL FRONT.
THE SURFACE BOUNDARY SHOULD PROVIDE AMPLE BOUNDARY LAYER CONVERGENCE
AND SHEAR TO SUPPORT ORGANIZED CONVECTION ALONG AND AHEAD OF IT
MONDAY AFTERNOON, MOST LIKELY A SQUALL LINE.  THE THERMODYNAMICS
WILL ALSO BE FAVORABLE FOR STRONG UPDRAFTS, WITH CAPES PROGGED TO
AROUND 2500 J/KG AGAIN. THUS, WILL CONTINUE TO ADVERTISE LIKELY POPS.

NO CHANGES TO THE EXTENDED.

.DTX...NONE.

MANN

MIZ075-082-083-280900-

HAZARDOUS WEATHER OUTLOOK FOR SOUTHEAST MICHIGAN
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
400 AM EDT SUN JUL 28 2002

...TORNADO WATCH NUMBER 541 HAS BEEN ALLOWED TO EXPIRE...

DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGERS IMMEDIATELY.

THUNDERSTORMS HAVE MOVED EAST OF THE WATCH AREA AND HAVE WEAKENED.
THEREFORE THE TORNADO WATCH THAT WAS IN EFFECT FOR
WASHTENAW...LENAWEE...AND MONROE COUNTIES HAS BEEN ALLOWED TO EXPIRE.

CONSIDINE