Severe Thunderstorm Warning 99, NWS Detroit, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
320 EDT FRI JUL 28 2000

LARGE CLOSED UPPER LEVEL LOW CIRCULATION WITH ITS CENTER OVER
CENTRAL LAKE MI PROGGED TO DRIFT SOUTH TO NORTHERN INDIANA BY SAT
EVE AND THEN LIFT SLOWLY NE TO SOUTHEAST LOWER MICHIGAN BY SUNDAY
EVE. WEAK ILL DEFINE SURFACE LOW SOMEWHERE OVER SOUTHERN LAKE MI IS
FORECAST TO REDEVELOP OVER CENTRAL ILLINOIS SATURDAY AND THEN LIFT
NORTHEAST TO ABOUT TOLEDO SUN EVE AND THEN LIFT SLOWLY NORTH WHILE
WEAKENING.

AS FAR AS THE FORECAST GOES FOR NEXT 48 HOURS...SHOWERS AND
THUNDERSTORMS DEVELOPING THIS AFTERNOON SHOULD GRADUALLY DIMINISH IN
INTENSITY AND COVERAGE OVERNIGHT.  AS OVERALL SYSTEM MOVES MORE TO
OUR SW...IT WILL PUT CWA IN THE COOLER AND MORE STABLE REGION.  WITH
ABUNDANT MOISTURE...A MORE SOLID OVERCAST SHOULD SETUP.  WITH THE
LACK OF SUNSHINE...WHATEVER ACTIVITY DEVELOPS SHOULD REMAIN LESS
INTENSE AND SMALLER IN COVERAGE.

AS SURFACE LOW APPROACHES LATE SATURDAY NIGHT AND SUNDAY...SHOWERS
AND THUNDERSTORMS WILL INCREASE IN COVERAGE AS OVERRUNNING PATTERN
SETUP. THIS SHOULD SPREAD INTO THE NORTHERN PORTIONS OF THE CWA BY
AFTERNOON.

AS FAR AS TEMPS GO...ON THE HIGHS SAT/SUN...WITH ABUNDANCE OF CLOUDS
AND COLDER SIDE OF SYSTEM FEEL FWC IS TOO HIGH.  ALSO...FAN HIGHS
LOOK A BIT TOO LOW BASED ON CURRENT TEMPS AROUND THE REGION. WILL GO
MORE WITH THE AVN MOS WHICH IS GIVING A COMPROMISE.

...EXTENDED...AS FAR AS THIS GOES...OVER PATTERN ACROSS CONUS STAYS
NEARLY THE SAME THROUGH AT LEAST WED WITH A SLIGHT WEAKENING OF
UPPER LEVEL TROF.  WILL NOT BE AN ALL DAY RAIN MON-WED BUT MORE OF A
MAINLY SCATTERED AFTERNOON TYPE ACTIVITY AS DAYTIME HEATING NEEDED
TO FIRE UP UNSTABLE ATMOSPHERE SINCE THERE IS A LACK OF ANY STRONG
LIFTING MECHANISM.

.DTX...NONE.

DRC

MIZ047>049-053>055-060>063-068>070-075-076-082-083-291200-

SEVERE WEATHER OUTLOOK FOR SOUTHEAST LOWER MICHIGAN
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1150 AM EDT FRI JUL 28 2000

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

DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGERS IMMEDIATELY.

THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND TONIGHT. THE
THUNDERSTORMS WILL BE MOST NUMEROUS LATE THIS AFTERNOON AND EARLY
THIS EVENING...AND WILL TEND TO BE MOST CONCENTRATED SOUTH OF A
FLINT TO PORT HURON LINE. A FEW OF THE STORMS COULD BE SEVERE THIS
AFTERNOON AND EARLY THIS EVENING...PRIOR TO 9 PM. THEREFORE...
SPOTTER ACTIVATION MAY BE NEEDED.

A VERY UNSTABLE AIRMASS OVER SOUTHEAST MICHIGAN THIS AFTERNOON WILL
GRADUALLY BECOME MORE STABLE TONIGHT. AS A RESULT...MORE
THUNDERSTORMS ARE EXPECTED THIS AFTERNOON AND TONIGHT. HOWEVER...STORMS
WILL BE MOST NUMEROUS LATE THIS AFTERNOON AND EARLY THIS
EVENING...DURING WHICH TIME THE STORMS WILL ALSO TEND TO BE
STRONGEST DUE TO DAYTIME HEATING. ISOLATED SEVERE STORMS THIS
AFTERNOON AND EARLY THIS EVENING COULD PRODUCE HAIL AS LARGE AS
DIMES...AND WIND GUSTS AS HIGH AS 50 MPH ARE ALSO POSSIBLE.
THUNDERSTORMS THIS AFTERNOON AND EARLY THIS EVENING WILL MOVE TOWARD
THE NORTHEAST AROUND 15 MPH...AND WILL PRODUCE HEAVY RAINFALL OF AS
MUCH AS AN INCH.

STAY TUNED TO NOAA WEATHER RADIO...OR YOUR FAVORITE MEDIA
OUTLET...FOR LATER FORECAST UPDATES...INCLUDING ANY NECESSARY
WATCHES OR WARNINGS.

DWD