Severe Thunderstorm Warning 95, NWS Detroit, MI

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

WILL HAVE TO PROVIDE THE CLIFF NOTES VERSION OF AN AFD THIS MORNING
DUE TO CURRENT RADAR TRENDS...

UPPER LOW WAS NEAR THE SRN PORTION OF THE YOOP EARLY THIS MORNING.
THIS VORTEX WILL CONTINUE TO BE THE MAIN PLAYER FOR SE LOWER THROUGH
THE SHORT AND MUCH OF THE LONG TERM AS IT MOVES SLOWLY SOUTH ACROSS
LM TODAY AND EVENTUALLY INTO NORTHERN IL BY SAT EVENING. MAIN AREA
OF CONVECTION HAS PERSISTED IN THE ERN HALF OF THIS SYSTEM WHICH IS
WHERE CWA REMAINS THROUGH THE PERIOD. SURFACE LOW WAS A LITTLE
FURTHER SOUTH OVER CENTRAL LM WITH TROF EXTENDING SE ACROSS SRN
PORTIONS OF CWA. MAJORITY OF ACTIVITY THU AFT AND EVENING WAS NORTH
OF THIS TROF. STILL QUITE A BIT OF ONGOING NOCTURNAL CONVECTION
ACROSS THE CENTRAL PART OF THE CWA AND THIS WILL HAVE TO BE DEALT
WITH AT PRESS TIME.

UNSTABLE AIRMASS WILL REMAIN IN PLACE THROUGH SATURDAY AS SYSTEM
DROPS S. SURFACE TROF PROGGED BY ETA/AVN TO SINK S THIS MORNING
WHICH MAY HELP FOCUS STORM DEVELOPMENT LATER TODAY FURTHER S THAN ON
THURSDAY. THE NORTHERN THUMB GOT POUNDED WITH SEVERAL INCHES OF
RAINFALL THURSDAY AND ADDITIONAL HEAVY RAINFALL WILL LIKELY RESULT
IN SOME FLOODING PROBLEMS. AS USUAL IN THIS SCENARIO, STORM
DEVELOPMENT AND EVOLUTION WILL BE DRIVEN ON THE MESO OR SMALLER
SCALE WHICH IF PRETTY TOUGH TO EVALUATE IN THE MIDDLE OF THE NIGHT.
LOOKS LIKE SOME DRIER AIR IN THE MID LEVELS WILL BE ADVECTING IN
BEHIND THE CURRENT CONVECTION. THIS WILL ALLOW FOR SOME SUNSHINE
THIS MORNING WHICH WILL DO NOTHING BUT MAKE FOR A MORE UNSTABLE
AIRMASS BY THIS AFTERNOON. MODEL SOUNDINGS WITH REPRESENTATIVE
PARCELS INDICATE 3000 J/KG POSSIBLE THIS AFTERNOON. WITH WEAK SHEAR
THIS SUGGESTS ANOTHER DAY OF PULSE SEVERE WITH POSSIBLE DIMES, OR
MAYBE QUARTERS, AND LOCALIZED AREAS OF HEAVY RAINFALL. MOISTURE
DEEPENS TONIGHT ALONG WITH ADDED BONUS OF SOME DEEP SYNOPTIC SCALE
LIFT. THESE FACTORS WILL PROBABLY RESULT IN AN INCREASE IN SHOWERS
AND STORMS BY EVENING, SIMILAR TO WHAT HAPPENED ON THURSDAY. AS
UPPER LOW CONTINUES TO SINK SOUTH, 50 KT 300MB JET ROUNDS THE BASE
AND NOSES INTO THE OH VALLEY BY 15Z/SAT. THIS PUTS SE LOWER IN LFQ
RESULTING IN SOME DECENT UPPER LEVEL DIVERGENCE. ETA/AVN QPFS QUITE
IMPRESSIVE ON SAT AS WELL. INSTABILITY NOT AS IMPRESSIVE THOUGH,
SO PERHAPS ANY STORMS WILL REMAIN BELOW SEVERE CRITERIA.

.DTX...NONE.

JW

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DETROIT/PONTIAC, MI
1108 PM EDT THU JUL 27 2000

TIME(EDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0323 PM    WASHINGTON                MI   .75 INCH HAIL
07/27/00   MACOMB

0325 PM    WASHINGTON                MI   1.00 INCH HAIL
07/27/00   MACOMB                         TRAINED SPOTTER REPORTED
                                          HAIL COVERED GROUND

0330 PM    WASHINGTON                MI   60 MPH TSTM WIND GUST
07/27/00   MACOMB

0738 PM    FOSTERS                   MI   .75 INCH HAIL
07/27/00   SAGINAW

0820 PM    LAPEER                    MI   .75 INCH HAIL
07/27/00   LAPEER

0831 PM    MT MORRIS                 MI   .75 INCH HAIL
07/27/00   GENESEE

0950 PM    OTTER LAKE                MI   .75 INCH HAIL
07/27/00   LAPEER

1043 PM    GAINES                    MI   .75 INCH HAIL
07/27/00   GENESEE

GSS

MIZ047>049-053>055-060>063-068>070-075-076-082-083-281200-

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

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

DISPATCHERS...PLEASE NOTIFY YOUR EMERGENCY MANAGERS IMMEDIATELY.

HEAVY AMOUNTS OF RAIN ASSOCIATED WITH THE THUNDERSTORMS WILL REMAIN
THE CONCERN THROUGH THE EARLY MORNING HOURS.  WHILE THEIR STILL IS A
THREAT FOR SOME OF THESE THUNDERSTORMS TO PRODUCE HAIL...THE MAIN
SEVERE WEATHER THREAT WILL BE FLOODING FOR THE REST OF THE NIGHT.
THEREFORE...SPOTTER ACTIVATION IS NOT EXPECTED.

A WARM...HUMID AND UNSTABLE AIR MASS COMBINING WITH SEVERAL SURFACE
BOUNDARIES WILL CONTINUE TO DEVELOP THUNDERSTORMS THROUGH THE EARLY
MORNING HOURS.  MANY AREAS IN THE SAGINAW VALLEY HAVE RECEIVED UP TO
THREE INCHES...WITH LOCALLY HIGHER AMOUNTS.  HOWEVER...THE RAIN IS
EXPECTED TO DIMINISH TOWARD DAWN.  ELSEWHERE EXPECT SCATTERED
THUNDERSTORMS...MAINLY NORTHWEST OF DETROIT...WITH LOCALLY HEAVY
RAIN POSSIBLE AND SMALL HAIL.

THUNDERSTORMS WILL MOVE OFF TO THE NORTHEAST BETWEEN 10 AND 15 MPH.
SOME OF THESE THUNDERSTORMS WILL MOVE ACROSS ALREADY SATURATED GROUND
WITH MORE FLOODING POSSIBLE.  RAINFALL RATES UP TO AN INCH PER HOUR
CAN BE EXPECTED.

STAY TUNED TO NOAA WEATHER RADIO...OR YOUR FAVORITE MEDIA OUTLET...
FOR LATER FORECAST UPDATES.

BGM