000 FXUS63 KMQT 101033 AFDMQT AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 533 AM EST WED FEB 10 2010 .SYNOPSIS... WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A STRONG SHORTWAVE/CLOSED LOW MOVING EAST THROUGH THE OHIO VALLEY. MOISTURE WRAPPING ON THE BACKSIDE OF THE THIS STORM SYSTEM ALONG WITH SOME Q-VECT CONV AND 700 FGEN FORCING HAS HELPED SUSTAIN LIGHT TO MODERATE SNOW SHOWERS ACROSS MUCH OF UPPER MI THIS MORNING. LAKE SUPERIOR ALSO PROVIDED SOME ENHANCEMENT TO SNOWFALL WITH 850 MB TEMPS AROUND -11C SUPPORTING LAKE DELTA-T OF AROUND 13C. LATEST 10Z RADAR IMAGERY REVEALS BAND OF MODERATE SNOW WITH AROUND 30 DBZ REFLECTIVITY RETURNS OVER DEERTON IN WRN ALGER COUNTY WHERE 700 MB FGEN FORCING IS MAXIMIZED. && .DISCUSSION... MODELS INDICATE THAT 700 MB FGEN FORCING COULD SUPPORT SOME MODERATE BANDS OF SNOW OVER ERN MQT AND WRN ALGER COUNTIES UNTIL AROUND 12Z THIS MORNING AND PERHAPS EVEN A BIT LONGER. HAVE HIGHLIGHTED THIS AREA FOR 3-4 INCHES OF LOCAL SNOW ACCUMULATION IN GRIDS. ELSEWHERE OVER THE HIGHER TERRAIN OF MQT COUNTY EXPECT UP TO 2 INCHES OF ADDITIONAL ACCUMULATION THIS MORNING BEFORE FORCING WEAKENS AND SNOW BEGINS TO TAPER OFF SOME THIS AFTERNOON. KEPT ADVISORY GOING FOR MQT COUNTY THIS MORNING AND ALSO ISSUED AN SPS FOR LOCALLY HEAVIER ACCUMS OVER FAR WRN ALGER COUNTY THROUGH THE MORNING COMMUTE. WEAK FORCING OVER ERN MQT AND WRN ALGER COUNTY COULD SUPPORT ANOTHER 1-2 INCHES OF LAKE ENHANCED SNOW THIS EVENING GIVEN MARGINALLY COLD TEMPS/INSTABILITY BUT THEN EXPECT SNOW TO TAPER OFF SOME OVERNIGHT AS DEEPER MOISTURE AND FORCING BEGINS TO LIFT EAST. SFC RDG AXIS AND ASSOC SUBSIDENCE MOVING OVER THE WRN COUNTIES SHOULD TAPER ANY LINGERING SNOW TO FLURRIES BY THU NIGHT AND FRI. LAKE INDUCED TROFFINESS AND CONVERGENT NW WIND FIELD WILL CONTINUE TO SUPPORT LIGHT ACCUMULATING SNOW SHOWERS OVER THE ERN COUNTIES THU INTO THU NIGHT BEFORE SNOW SHOWERS GENERALLY TAPER TO FLURRIES BY LATE FRI MORNING WITH INCREASED RDGG FROM THE WEST AND LOWERING OF SUBSIDENCE INVERSION. && .AVIATION /FOR THE 06Z TAFS/... DRIER AIR IS STARTING TO COME INTO THE CWA AS THE FRINGE OF THE STORM SYSTEM ROLLING INTO THE OHIO VALLEY STARTS TO MOVE AWAY. AT KCMX...MVFR CONDITIONS WILL CONTINUE NRLY FLOW IS TYPICALLY NOT THE FAVORABLE DIRECTION FOR HEAVIER SNOW OFF THE LAKE OR LOW CIGS AT KCMX. AT KSAW...N FLOW WILL BE IDEAL FOR TERRAIN ENHANCED SNOW OFF THE LAKE...BUT DRY AIR IS STARTING TO WORK IN NOW AND WILL CONTINUE TO AFFECT THE AREA. MVFR CONDITIONS SHOULD DOMINATE FOR THE MOST PART. THERE MAY BE SOME PERIODS OF IFR EARLY THIS MORNING IN HEAVIER SNOW AREAS. THIS DRIER AIR SHOULD KEEP THINGS MVFR WITH A N UPSLOPE FLOW. && .MARINE /FOR THE 4 AM LAKE SUPERIOR ISSUANCE/... 25 TO 30KT NNE WINDS WILL CONTINUE THROUGH THIS AFTERNOON...AND CONTINUE THROUGH THIS EVENING EAST...AS LOW PRESSURE JUST OFF THE COAST OF DELAWARE WILL RAPIDLY DEEPEN TO OFF LONG ISLAND BY EARLY THURSDAY. MEANWHILE...HIGH PRESSURE STRETCHING FROM HUDSON BAY THROUGH EASTERN TEXAS THIS MORNING CAN BE EXPECTED TO STRETCH FROM HUDSON BAY THROUGH THE MISSISSIPPI RIVER VALLEY BY THURSDAY AFTERNOON. BY SATURDAY...EXPECT THIS ELONGATED AREA OF HIGH PRESSURE TO SPLIT...LEAVING STRONGER HIGH PRESSURE OVER HUDSON BAY...AND WEAKENING HIGH PRESSURE OVER THE TENNESSEE VALLEY. LOW PRESSURE OVER THE CENTRAL TO NORTHERN PLAINS SATURDAY MAY SHIFT OVER ILLINOIS AND INDIANA SUNDAY...AS STRONG HIGH PRESSURE SINKS FROM CENTRAL CANADA TO THE NORTHERN PLAINS. N WINDS WILL ONCE AGAIN INCREASE TO NEAR 30KTS SUNDAY AFTERNOON THROUGH MONDAY MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR MIZ005. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 1 PM EST /NOON CST/ THIS AFTERNOON FOR LSZ162-263>267. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...VOSS DISCUSSION...VOSS AVIATION...KF MARINE...KF