Severe Thunderstorm Warning 1, NWS Gaylord, MI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
340 PM EDT WED APR 11 2001

RIDGING OVER GREAT LAKES REGION BREAKING DOWN WITH APPROACH OF
STRONG UPPER LOW CURRENTLY IN THE CENTRAL PLAINS. LOW MOVES INTO
ONTARIO THURSDAY NIGHT WITH A MORE ZONAL UPPER FLOW TO FOLLOW. AT
THE SURFACE...OCCLUDED LOW OVER THE PLAINS APPROACHING REGION WILL
CONTINUE SHOWERS AND THUNDERSTORMS INTO THURSDAY. HIGH PRESSURE THEN
MAKES A BRIEF APPEARANCE FRIDAY BEFORE A WEAK LOW APPROACHES FROM
THE WEST. PROBLEM FOR THE FORECAST PERIOD IS SEVERE THREAT TONIGHT
AND WHETHER TO CARRY POPS THURSDAY INTO THURSDAY NIGHT.

TONIGHT...WARM FRONT MOVING NORTH REACHES REGION LATE THIS EVENING
WITH COLD FRONT ARRIVING IN THE EARLY MORNING HOURS. GOOD DYNAMICS
WITH LEFT EXIT REGION OF 120KT UPPER JET MOVING IN. PROBLEM IS HOW
FAR NORTH WARM FRONT WILL BE ABLE TO PROGRESS ALLOWING UNSTABLE AIR
TO MOVE IN. RAIN COOLED AIR AND LAKE HURON EFFECT MAY SLOW DOWN THE
FRONT PRETTY WELL OVERNIGHT. IF THIS IS THE CASE...SOUTHWEST PART OF
FORECAST AREA WOULD HAVE BEST CHANCE OF THUNDERSTORMS WHERE CAPES
FORECAST TO RISE TO AROUND 1K J/KG. WITH WIND FIELDS RUNNING AROUND
50 TO 55KT AT 850MB WILL NOT TAKE MUCH TO MIX DOWN STRONG WINDS.
HOWEVER...BEST CHANCES WILL BE SOUTH OF REGION.

THURSDAY...DRY SLOT OVER MUCH OF REGION BY 12Z WITH COLD FRONT
EXTENDING OVER LAKE HURON TO CVG. ETA SOUNDINGS STILL INDICATE CAPES
OVER 1K J/KG ON THE EAST SIDE OF REGION AS LOW LEVELS WILL TAKE
LONGER TO DRY OUT. STILL COULD SEE A THUNDERSTORM DEVELOP BUT MOST
LIKELY WILL BE EAST OF REGION. COULD BE SOME EARLY MORNING
SUN...THEN WRAPAROUND PRECIPITATION THEN MOVES IN WITH LOW
CENTER...LOOKS LIKELY ACROSS EASTERN UPPER WITH DECREASING CHANCES
FARTHER SOUTH. ETA MAY BE CARRYING TOO MUCH DEEP MOISTURE SOUTH OF
THE LOW...AVN MAY HAVE A BETTER HANDLE ON THIS ESPECIALLY WITH
TIGHTLY WOUND SYSTEM.

THURSDAY NIGHT WILL BE MUCH THE SAME WITH AT LEAST CLOUDS AROUND AND
BEST CHANCE OF PRECIPITATION FROM NORTH TO SOUTH.

THEN FRIDAY...WEAK RIDGING BEHIND UPPER LOW APPROACHES AS UPPER FLOW
BEGINS TO GET MORE ZONAL. HIGH PRESSURE MOVES IN WITH 850MB TEMPS
WILL BE RUNNING JUST UNDER 0C. STRONG APRIL SUNSHINE SHOULD BE ABLE
TO PUSH TEMPS CLOSE TO NORMAL.

.EXTENDED...
ZONAL FLOW EXPECTED THROUGH THE WEEKEND. FLOW BECOMES MORE AMPLIFIED
AS RIDGE BUILDS IN THE WEST...TROUGH MOVING THROUGH GREAT LAKES
AROUND SUNDAY/MONDAY EVENTUALLY CARVES OUT DEEP TROUGH IN THE
EASTERN PART OF COUNTRY. WILL CARRY PRECIPITAITON CHANCES AS TROUGH
APPROACHES AND CROSSES REGION...WITH BELOW NORMAL TEMPERATURES
EXPECTED NEXT WEEK.

.APX...NONE.

FARINA

MIZ031>034-120415-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GAYLORD MI
720 PM EDT WED APR 11 2001

THE STORM PREDICTION CENTER HAS ISSUED A TORNADO WATCH FOR PORTIONS
OF NORTHERN MICHIGAN EFFECTIVE UNTIL MIDNIGHT EDT. THIS WATCH
INCLUDES THE FOLLOWING COUNTIES

IN NORTHERN LOWER MICHIGAN
     ROSCOMMON...WEXFORD...MISSAUKEE AND MANISTEE

THIS WATCH INCLUDES THE ADJOINING COASTAL WATERS OF AFFECTED
LAKESHORE COUNTIES.

A TORNADO WATCH MEANS THAT CONDITIONS ARE FAVORABLE FOR THE
DEVELOPMENT OF THUNDERSTORMS CAPABLE OF PRODUCING TORNADOES. IF YOU
LIVE IN OR NEAR THE WATCH AREA...YOU SHOULD REMAIN ALERT TO RAPIDLY
CHANGING WEATHER CONDITIONS. STAY TUNED TO NOOAA WEATHER RADIO OR
LOCAL TELEVISION OR RADIO STATIONS FOR FURTHER UPDATES AND POSSIBLE
WARNINGS.

ROWLEY