Severe Thunderstorm Warning 63, NWS Detroit, MI

SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1010 AM EDT THU AUG 9 2001

COMPLEX OF STORMS APPROACHING THE SOUTHERN COUNTIES AND CONTINUE TO
REMAIN HEALTHY.  CLOUD TOPS CONTINUE TO COOL AND MOVEMENT IS
NORTHEAST.  THIS IS ALONG THE LEADING EDGE OF THE MOISTURE REMAINS
FROM T.S. BARRY AND IMPRESSIVE 700MB THETA-E ADVECTION (GRADIENT
MAGNITUDE IS EQUALLY IMPRESSIVE).  THIS WILL BE THE FIRST PROBLEM OF
THE DAY...

WITH COMPLEX APPROACHING...THIS WILL LIKELY HOLD DOWN TEMPS AND HEAT
INDEX VALUES ALONG AND SOUTH OF I-94.  HOWEVER IF COMPLEX MOVES EAST
BEFORE NOON...PLENTY OF SUNSHINE BEHIND IT (PER LATEST VISIBLE
SATELLITE) AND DEWPOINTS WILL BE QUITE A BIT HIGHER FROM THE
RAINFALL (MID TO UPPER 70S).  WE WILL LEAVE IN THE HEAT INDEX
HEADLINE.  THIS MAY LEAVE BEHIND BOUNDARIES (OUTFLOW AND
DIFFERENTIAL HEATING) THAT WILL BE MONITORED CLOSELY.  (IE...NEW
SCAN NOW SHOWS LEADING ACTIVITY WEAKENING)

SOUNDINGS UPSTREAM...UNSTABLE.  CAPES BETWEEN 3000/4000 J/KG AND
SATELLITE DERIVED LI/S -2C TO -4C.  MID LEVEL FLOW WILL GRADUALLY
INCREASE BRINGING THE THREAT OF SEVERE WEATHER (WIND) TO OUR CWA.
PRE FRONTAL TROF AS NOTED IN THE HI-RES VISIBLE AND MSAS IS MOVING
ACROSS LOWER WISCONSIN AND NORTHERN LOWER MICHIGAN.  88D/S NOW
PICKING UP REFLECTIVITIES ACROSS LAKE MICHIGAN AS THIS MAY BE THE
START FOR AN ACTIVE AFTERNOON.  NEW RUC NOW SHOWS PRE-FRONTAL TROF
(IN ASSOCIATION WITH THAT CU FIELD) MOVING INTO THE NORTHWEST CWA
BETWEEN 16Z-18Z.  WILL BRING THE CHANCE OF STORMS EARLIER IN THE NEW
ZONES.  WE HAVE INITIATED RSO FROM 1526Z-0026Z.

POTENTIAL FOR A SQUALL LINE TONIGHT WITH THE COLD FRONT AS RAIN
LOOKS LIKE A GOOD BET (WE ALL NEED IT).  WE ARE UNDER THE INFLUENCE
OF 300MB RRQ AND MID LEVEL FLOW NEAR 50 KTS.  AGAIN WIND THE MAIN
THREAT TONIGHT BEFORE OUR BIG BREAK FRIDAY.

QUESTIONS OR COMMENTS ARE WELCOME.  NEW ZONES...NPW...SPS WILL BE
OUT SHORTLY.

.DTX...HEAT ADVISORY TODAY ALL OF SOUTHEAST MICHIGAN.

BGM

MIZ047>049-053>055-060>063-068>070-075-076-082-083-100400-

SEVERE WEATHER OUTLOOK FOR SOUTHEAST LOWER MICHIGAN
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1111 AM EDT THU AUG 9 2001

...SEVERE WEATHER POTENTIAL STATEMENT FOR SOUTHEAST MICHIGAN...

DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGERS IMMEDIATELY.

SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON... HOWEVER A
LINE OF THUNDERSTORMS IS EXPECTED TO APPROACH TOWARD THIS EVENING.
SOME OF THESE THUNDERSTORMS WILL BECOME SEVERE WITH WIND GUSTS OVER
60 MPH. SPOTTER ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND
TONIGHT.

A STRONG COLD FRONT ACROSS THE NORTHERN PLAINS STATES WILL PUSH
SOUTHEAST TOWARD THE REGION THIS AFTERNOON AND TONIGHT.  IN ADVANCE
OF THIS COLD FRONT IS A TROUGH OF LOW PRESSURE THAT WILL INITIALLY
HELP WITH THE DEVELOPMENT OF THUNDERSTORMS ACROSS THE TRI CITIES
REGION EARLY THIS AFTERNOON. FURTHERMORE...MOISTURE FROM THE REMNANTS
OF TROPICAL STORM BARRY IS AIDING IN THE DEVELOPMENT OF THUNDERSTORMS
ACROSS MONROE AND LENAWEE COUNTIES...BUT THESE THUNDERSTORMS ARE NOT
EXPECTED TO BECOME SEVERE.

THE SEVERE WEATHER THREAT ACROSS ALL OF SOUTHEAST LOWER MICHIGAN WILL
BE PRIMARILY BETWEEN 1 PM AND MIDNIGHT.  AT THIS TIME...
THUNDERSTORMS ARE EXPECTED TO DEVELOP NORTH OF INTERSTATE 69
BETWEEN 1 PM AND 4 PM...DEVELOPING FURTHER SOUTH IN THE CORRIDORS
OF INTERSTATE 69 AND 94 BETWEEN 4 PM AND 7 PM.  SHOWERS AND
THUNDERSTORMS ALONG AND SOUTH OF INTERSTATE 94 WILL CONTINUE
THROUGH THE AFTERNOON PERHAPS REACHING NEAR SEVERE LEVELS LATE THIS
AFTERNOON.

THUNDERSTORMS WILL INITIALLY MOVE EAST BETWEEN 10 AND 15 MPH.  TOWARD
EVENING THUNDERSTORM MOVEMENT WILL BE TOWARD THE SOUTHEAST AND
INCREASE IN FORWARD SPEED BETWEEN 15 AND 25 MPH.  THUNDERSTORMS ARE
EXPECTED TO CLEAR SOUTHEAST LOWER MICHIGAN AFTER MIDNIGHT.

STAY TUNED TO NOAA WEATHER RADIO...OR TO YOUR FAVORITE MEDIA
OUTLET...FOR LATER WEATHER UPDATES. YOU CAN ALSO REACH YOUR NATIONAL
WEATHER SERVICE ONLINE AT
HTTP://WWW.CRH.NOAA.GOV/DTX/START.HTM (ALL LOWER CASE)

BGM