Heavy Snow in Michigan, March 5 to 6, 2001

SOUTHEAST MICHIGAN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1035 AM EST MON MAR 5 2001

SATELLITE IMAGERY SHOWS SKY CONDITIONS CU-ING UP AS THE MARCH SUN WORKS
ON THE BOUNDARY LAYER UNDER COLD TEMPS ALOFT. THIS WILL RESULT IN
SCATTERED LIGHT SNOW SHOWERS IN ADVANCE OF THE LOW PRESSURE SYSTEM
OVER NORTHERN LOWER. THIS SYSTEM IS ALSO SHOWN CLEARLY ON VISIBLE
AND IR SATELLITE IMAGERY WITH ITS IMPRESSIVE UPPER CIRCULATION. THE
UPPER AIR RUNS HAVE LED TO A DEEPER INITIALIZATION OF THE LOW IN THE
12Z MODELS, INCLUDING A DRAMATIC STRENGTHENING OF THE VORTICITY
CENTER. THEY SHOW THE SYSTEM STILL ON TRACK AS FAR AS TIMING THROUGH
SE MICHIGAN THIS AFTERNOON, AND STILL SHOW THE MAIN PRECIPITATION
AREA ON THE NORTH FLANK WHERE STRONG ISENTROPIC LIFT AND MOISTURE
ADVECTION WILL OCCUR.

FOR THE AFTERNOON UPDATE, PLAN TO KEEP ACCUMULATION IN THE 1 TO 2
INCH RANGE FOR THE SAGINAW VALLEY, BUT MONITOR THE SITUATION FOR
LOCALLY HIGHER AMOUNTS. THE KAPX RADAR HAS SHOWN A FEW BANDS OF
HIGHER REFLECTIVITY WRAPPING AROUND THE SYSTEM, WHICH ARE CAPABLE OF
HIGH SNOWFALL RATES, ESPECIALLY SINCE THE AIR MASS IS ON THE COLD
SIDE. A BOOST FROM LAKE MICHIGAN IS ALSO LIKELY TO CONTRIBUTE EVEN
AS FAR EAST AS THE TRI CITIES, HOWEVER, MORE LIKELY LATER FROM LAKE
HURON. THE TIMING OF WIDESPREAD SNOW STILL LOOKS GOOD FOR LATER IN
THE AFTERNOON, AROUND 2 PM FOR FLINT AND 4 PM FOR DETROIT=.

.DTX...GALE WARNING...TONIGHT AND TUESDAY...LAKE HURON.

BT