000 FXUS63 KMQT 241130 AAA AFDMQT AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE MARQUETTE MI 630 AM EST TUE NOV 24 2009 UPDATED FOR 12Z TAF ISSUANCE .DISCUSSION... .TODAY AND TONIGHT...EXPECT AREAS OF DRIZZLE TO PERSIST OVER THE MAJORITY OF UPPER MICHIGAN THROUGH THIS MORNING AND PERHAPS INTO THE AFTERNOON...ESPECIALLY IN UPSLOPE AREAS WHERE MOIST SOUTHEASTERLY FLOW IS OCCURRING. A QUICK LOOK AT VISIBILITIES AROUND UPPER MICHIGAN THOUGH SHOWS CONDITIONS ARE AS BAD AS PREVIOUS NIGHTS. BUFKIT PROFILES INDICATE A LOT OF LOW LEVEL MOISTURE PRESENT WITH DRYING ALOFT...LIKELY AIDING DRIZZLE DEVELOPMENT. LOWERED HIGHS A BIT TODAY TOO WITH DRIZZLE EXPECTED MOST OF THE DAY. .WEDNESDAY THROUGH THURSDAY...LOW PRESSURE CURRENTLY OVER EASTERN KANSAS WILL TRACK TO TVC BY WEDNESDAY AFTERNOON. FAIRLY POTENT SYSTEM ALREADY WITH LIGHTNING NOTED ON LATEST SFC OBSERVATIONS NEAR THE LOW CENTER...LIKELY AIDED BY DEW POINTS AROUND 50. THE LOW STRENGTHENS SLIGHTLY AS IT TRACKS TOWARDS US...HOWEVER LACK OF COLD AIR WILL PRECLUDE ACCUMULATING SNOW FROM FALLING. THE EXCEPTION IS OVER THE HIGHER TERRAIN OF WESTERN UPPER MICHIGAN WHERE WET BULB ZERO HEIGHTS WILL BE LOW ENOUGH TO SUPPORT MOSTLY SNOW. NOT OUT OF THE QUESTION A INCH OR TWO OF WET SNOW COULD ACCUMULATE THERE WEDNESDAY NIGHT INTO THURSDAY MORNING. LATEST SREF FIELDS AGREE THAT SNOW WILL HOLD OFF THERE UNTIL AROUND 06Z THURSDAY. OPTED FOR AN ALL RAIN FORECAST FOR AREAS EAST OF LINE FROM MQT TO IMT THROUGH THURSDAY MORNING THEN MIXED IN SNOW THEREAFTER AS CRITICAL THICKNESS VALUES ARE REALIZED CWA WIDE BY 03Z FRIDAY. FOR THE MOST PART MAINTAINED GOING FORECAST OF LIKELY POPS BUT ADJUSTED HIGHERS POPS ON THURSDAY TO DEFORMATION AREA AS THE SFC LOW PASSES TO THE SOUTHEAST OF UPPER MICHIGAN. SOME CONCERN ABOUT PRECIPITATION WEDNESDAY AFTERNOON/EVENING AS INITIAL S/W DEPARTS OUT OF ILLINOIS AND A SECOND S/W DIGS IN BEHIND IT. MODELS HINT AT A LULL IN THE PRECIPITATION DURING THIS TRANSITION TIME. THE LAST COUPLE RUNS OF THE GFS HAVE THE EAST HALF OF UPPER MICHIGAN NEARLY DRY...SOMETHING THE LATEST ECMWF...00Z/24...NOW SHOWS TO AN EXTENT. OPTED TO TREND POPS LOWER OVER EASTERN ZONES ON WEDNESDAY NIGHT AS A RESULT. THINK THIS WILL NEED TO BE REFINED A BIT MORE BY LATER SHIFTS. .THURSDAY NIGHT AND FRIDAY...NORTHERLY FLOW BEHIND THE SYSTEM WILL ALLOW FOR SOME LAKE EFFECT SNOW AS 850MB TEMPERATURES LOOK COLDER THAN YESTERDAY/S MODEL RUNS...THOUGH BE IT MARGINAL. DEEP MOISTURE EXITS QUICKLY THOUGH SO NOT ANTICIPATING MUCH ACCUMULATION. SURFACE/MID LEVEL RIDGING SHIFTS INTO UPPER MICHIGAN FOR FRIDAY NIGHT ENDING ANY ONGOING LES. && .AVIATION /FOR THE 12Z TAF ISSUANCE/... IN THE ABSENCE OF ANY LLVL MSTR ADVECTION...EXPECT IFR CIGS/VSBY AT SAW THIS MRNG TO IMPROVE WITH SOME DAYTIME HEATING. MVFR CIGS AT BOTH SITES WL PREDOMINATE TDAY INTO THIS EVNG WITH HIER RH AT TOP OF SHALLOW MIXED LYR LINGERING AT INVRN BASE ARND H9 SHOWN ON LOCAL 00Z RAOBS. NOCTURNAL COOLING MAY RESULT IN SOME FOG FORMATION TNGT... BUT CONTINUED LACK OF LLVL MSTR ADVECTION AND PERSISTENT OVC THAT WL LIMIT THE TEMP FALL SUGS THE FOG WL NOT BECOME THAT THICK WITH ONLY MVFR VSBYS. THE ONLY EXCEPTION MAY BE AT SAW LATE TNGT...WHERE SOME -RA IS LIKELY TO ARRIVE AND MOISTEN THE LLVLS IN THE PRESENCE OF UPSLOPE SE FLOW. && .MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/... EXPECT HI PRES OVER THE CANADIAN MARITIMES TO REMAIN NEARLY STATIONARY THROUGH WED AS LO PRES ORGANIZING OVER THE CENTRAL PLAINS LIFTS NE TO NEAR THE STRAITS OF MACKINAC LATE IN THE DAY. WINDS SHOULD REMAIN AOB 20 KTS INTO WED BEFORE INCREASING LATER IN THE DAY. THIS LO WILL GRADUALLY CONSOLIDATE WITH A DEEPER LO PRES SYSTEM DEVELOPING OFF THE NEW ENGLAND COAST ON FRI. EXPECT A PERIOD OF N WINDS TO 30 KTS ON THU WITH SHARPENING PRES GRADIENT OVER LAKE SUPERIOR ON THE NW FLANK OF THE LO. LOOK FOR A HI PRES RIDGE TO MOVE INTO THE GREAT LAKES ON LATE FRI AND SAT. AS THE LO SHIFTS TO THE E AND THIS RIDGE MOVES IN FROM THE W...WINDS WILL DECREASE STEADILY ON FRI/SAT. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...PEARSON AVIATION...KC MARINE...KC