Flood in Michigan, February 10 to 13, 2001

SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
325 PM EST SAT FEB 10 2001

COMBINATION OF LAKE EFFECT CLOUDS AND FLURRIES AND INSTABILITY
CLOUDS CONTINUE TO STREAM ACROSS SOUTHEAST MICHIGAN. BELIEVE THAT
THE INSTABILITY CLOUDS WILL BEGIN TO DISSIPATE AROUND SUNSET LEAVING
PARTLY CLOUDY CONDITIONS... AND THEN THE LAKE EFFECT CLOUDS AND
FLURRIES WILL BACK UP TOWARDS LAKE MICHIGAN AS THE WINDS DECREASE
AND DRIER AIR WORKS INTO THE BOUNDARY LAYER. THIS SHOULD LEAVE MOSTLY
CLEAR CONDITIONS ACROSS THE ALL OF SOUTHEAST MICHIGAN BY MIDNIGHT.
WARM ADVECTION MID CLOUDS TO THE WEST OF MICHIGAN ARE HEADING TO
EAST AND SHOULD BE REACHING SOUTHEAST MICHIGAN TOWARDS SUNRISE.
THESE CLOUDS WILL BE ADVECTING INTO A DRY AIRMASS AND SOME OF THEM
SHOULD DISSIPATE PRIOR TO REACHING THE FORECAST AREA. AT THIS POINT
WILL CARRY A MOSTLY CLEAR FORECAST FOR THE OVERNIGHT PERIOD AND THEN
GO WITH PARTLY SUNNY ON SUNDAY DUE TO THE WARM ADVECTION MID CLOUDS
IN THE MORNING AND INCREASING HIGH CLOUDINESS IN THE AFTERNOON.

WARM ADVECTION ALOFT CONTINUES SUNDAY NIGHT AND AN INVERSION
DEVELOPS. QUITE A BIT OF LOW LEVEL MOISTURE WILL BE TRAPPED BELOW
THIS INVERSION AND FEEL THAT THE COMBINATION OF THE LOW LEVEL
MOISTURE AND INCREASING MID AND HIGH LEVEL MOISTURE WILL BE ENOUGH TO
GIVE MOSTLY CLOUDY CONDITIONS TO SOUTHEAST MICHIGAN. SOME WEAK
UPWARD MOTION IS FORECAST FOR THE NORTHERN SECTION OF THE FORECAST
AREA LATE SUNDAY NIGHT AND 6KM ETA DOES PRINT OUT A LITTLE PRECIPITATION.
22KM ETA DOES SHOW THE INCREASING MID LEVEL MOISTURE... BUT IT ALSO
HAS A DRY LAYER AROUND 850MB. THE DRY AIR OVER SOUTHEAST MICHIGAN
NOW WILL BE SLOW TO MOVE OFF TO THE EAST AND A TYPICAL SCENARIO
WOULD BE TO END UP WITH A SOUNDING SIMILAR TO THE ONE FROM THE 22KM
ETA. WILL LEAN TOWARDS THE 22KM ETA SOLUTION AND NOT MENTION ANY
SNOW FOR SUNDAY NIGHT ACROSS THE NORTH.

NEXT SHORT WAVE WILL STAY WELL NORTH OF THE REGION MONDAY. BETTER
LIFT AND MOISTURE WILL PASSES NORTH OF THE FORECAST AREA AND ALL WE
SHOULD SEE IS JUST CLOUDS.

WILL HAVE TEMPERATURES WITHIN A COUPLE DEGREES OF THE MAV VALUES FOR
TONIGHT THROUGH SUNDAY NIGHT. BELIEVE THAT THE MAV WARMS THINGS UP
TOO FAST FOR MONDAY GIVEN THE AMOUNT OF CLOUDINESS EXPECTED. FWC
APPEARS TO BE MORE REASONABLE AND WILL HAVE HIGHS ON MONDAY LEANING
TOWARDS THESE VALUES.

FOR THE EXTENDED...
MRF AND ETAXX NOT TOO DIFFERENT THROUGH THE END OF THE WEEK WITH
EACH SHOWING A COLD FRONT MOVING ACROSS LOWER MICHIGAN LATE TUESDAY.
AIRMASS WARMS UP ENOUGH TO WARRANT TO KEEP A CHANCE OF RAIN AND SNOW
IN THE FORECAST.

TEMPERATURES BEHIND THE COLD FRONT DROP OFF QUITE A BIT WITH 850MB
VALUES FALLING TO AROUND MINUS 16 OVER NORTHERN LAKES MICHIGAN AND
HURON. THIS WILL BE COLD ENOUGH TO GET THE LAKE EFFECT SNOW SHOWERS
GOING... THUS WILL ADD A CHANCE OF SNOW SHOWERS AND FLURRIES TO THE
FORECAST.

BOTH MRF AND ET-XX SHOW A STORM SYSTEM LIFTING OUT OF THE SOUTHWEST
LATE THURSDAY AND PASSING SOUTH OF MICHIGAN ON FRIDAY. TREND OF THIS
SYSTEM HAS BEEN TO TAKE IT ON A TRACK A LITTLE FURTHER TO THE NORTH
AND SLOW IT DOWN. PRESENT TRACK WOULD TAKE IT FROM ARKANSAS TO NEAR
CLEVELAND. GIVEN THAT IT IS STILL 6 DAYS AWAY THERE WILL PROBABLY BE
ADDITIONAL CHANGES IN THE TRACK OF THIS SYSTEM. AT THIS POINT WILL
CARRY A CHANCE OF RAIN AND SNOW FOR FRIDAY. COLD AIR FLOODS INTO THE
REGION FOLLOWING PASSAGE OF THIS LOW... THUS WILL HAVE A CHANCE OF
SNOW SHOWERS AND FLURRIES IN THE FORECAST FOR SATURDAY.

.DTX...NONE.

KEYES