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000 FXUS63 KMKX 100125 AAB AFDMKX AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 725 PM CST TUE MAR 9 2010 .SHORT TERM...EXTENDED DENSE FOG ADVISORY FOR MARINE ZONES UNTIL 16Z WEDNESDAY MORNING...AND EXTENDED IT SOUTHWARD TO WIND POINT. WINDS HAVE BEEN A LITTLE SLOWER TO COME UP THAN EXPECTED AND WEB CAMS SHOWED LOW VSBYS OFFSHORE BEFORE DARK. MIXING DUE TO INCREASING WINDS EXPECTED TO IMPROVE VSBYS ABOVE 1/4 MILE BY 12Z- 14Z WED...BUT WITH HIGHER DEW POINT AIR BEING ADVECTED OVER THE COOLER WATERS...WANTED TO EXTEND ADVISORY AND PROVIDE A CUSHION IN CASE CONDENSATION OF THIS MORE MOIST AIR MASS OFFSETS MIXING AND KEEPS DENSE FOG IN PLACE. WEDGE OF CLEAR/PARTLY CLOUDY SKIES MOVING OVER CWA IN WAKE OF INITIAL BAND OF LIGHT RAIN IS NARROWING AS NEXT SHORT WAVE...AND ASSOCIATED SCATTERED SHOWERS...APPROACHES FROM THE SOUTHWEST. WILL WATCH FOR ANY AFFECT ON FOG THIS OPENING MAY HAVE BEFORE CLOUDS FILL BACK IN...BUT AREAS OF FOG IN GOING FORECAST APPEARS TO COVER IT WELL. && .PREV DISCUSSION... /ISSUED 505 PM CST TUE MAR 9 2010/ TONIGHT AND WEDNESDAY MORNING...CONFIDENCE HIGH UPPER LOW OVER THE CENTRAL PLAINS THIS AFTERNOON WITH TWO DISTINCT EMBEDDED SHORT WAVE CIRCULATIONS. ONE ROTATING ACROSS CNTRL AND WRN NEBRASKA. THE OTHER HEADING NORTHEAST INTO MISSOURI. THIS SECOND ONE REPRESENTS OUR FIRST BEST CHANCE OF A MODERATE ROUND OF RAIN FOR THE CWA LATER TONIGHT AND WEDNESDAY MORNING. THERE IS A LEADING BAND OF QPF ROLLING THROUGH THIS AFTERNOON...BUT IT SLOWLY ERODES AS IT MOVES OUT AHEAD OF ITS MAIN SUPPORT. LOOKS LIKE THERE WILL BE A LULL IN THE ACTION FOR THE EVENING HOURS. HEAVY POPS RETURN AFTER MIDNIGHT AND CONTINUE TO WEDNESDAY MORNING AS THE SHORT WAVE OVER MO LIFTS NORTH INTO THE AREA. WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT...FORECAST CONFIDENCE MEDIUM. THIS PERIOD STILL LOOKS QUIET. IT IS ANOTHER LULL BETWEEN SPOKES OF ENERGY ROTATING AROUND THE UPPER LOW TO THE SOUTHWEST. THE FIRST UPPER LOW ACTUALLY WEAKENS AND LIFTS NORTH...THEN NORTHWEST WHILE ANOTHER VIGOROUS SHORT WAVE DIGS THROUGH THE CENTRAL PLAINS. WE ACTUALLY GET INTO SOME WEAK SHORT WAVE RIDGING FOR WEDNESDAY NIGHT. SO...ONLY VERY LIGHT QPF EXPECTED THIS PERIOD. THURSDAY AND THURSDAY NIGHT...FORECAST CONFIDENCE LOW TO MEDIUM. THE SECOND SHORT WAVE THAT DIGS INTO THE CENTRAL PLAINS MERGES WITH THE FIRST SHORT WAVE THAT LIFTED NORTH TO CREATE ONE HUGE UPPER LOW CENTERED AROUND MISSOURI. THE FIRST OF A FEW MORE WAVES OF QPF WILL ARRIVE WITH A SPOKE OF VORTICITY LATER THURSDAY MORNING INTO THURSDAY NIGHT. THERE IS AN IMPRESSIVE SURGE OF MOISTURE AND WARMER TEMPS ON A STRONG LLV JET WITH STRONG OMEGA ACCOMPANYING ALL THIS. THIS COULD RESULT IN THE HIGHEST QPF OF THIS EVENT. 1/2 TO 1 INCH AMOUNTS ARE POSSIBLE. BEYOND THURSDAY NIGHT...FORECAST CONFIDENCE LOW. THE UPPER LOW WILL CONTINUE TO SPIN AND VERY SLOWLY DRIFT EAST. IT MAY TAKE UNTIL EARLY NEXT WEEK TO GET OUT OF HERE. SO MORE RAIN IS EXPECTED FROM TIME TO TIME BUT THE MODELS REALLY BEGIN TO DIVERGE ON TIMING IN THESE OUT PERIODS. NOT SURPRISING GIVEN THE NATURE OF THIS MASSIVE CLOSED LOW. THESE OLD LOWS START GETTING ALL WRAPPED WITH A MIX OF DRY AND MOIST AIR AND IT MAKES TIMING EXTREMELY DIFFICULT. PRECIP WILL REMAIN IN THE FORECAST THROUGH THE WEEKEND. TEMPS THROUGH THE FORECAST PERIOD WILL BE HEAVILY INFLUENCED BY THE COLD WATERS OF LAKE MICHIGAN...ESPECIALLY OVER THE ERN CWA...WHEN THE WINDS ARE ONSHORE. MOS GUIDANCE IS NOT GIVING THAT COLD LAKE ENOUGH CREDIT AND WILL HACK TEMPS THERE AS NEEDED. AVIATION...A BRIEF AREA OF LIGHT RAIN SHOWERS PASSING THROUGH THE REGION THIS AFTERNOON SHOULD BE NORTH OF THE CWA BY 00Z THIS EVENING. CIGS WITH THE RAIN AND JUST BEHIND ARE EXPECTED TO STAY VFR. VSBYS WILL MOST LIKELY REMAIN MVFR WITH LIGHT FOG AND HAZE ACROSS THE REGION. HOWEVER...THERE IS A LOT OF UNCERTAINTY IN VSBYS TONIGHT BECAUSE OF THE MOIST SE FLOW. THE DIFFERENCE BETWEEN LAST NIGHT AND TONIGHT IS THAT THERE WILL BE WINDS TO KEEP THE BNDRY LAYER MIXED ENOUGH TO KEEP FOG FROM BECOMING DENSE. THEREFORE...LOWEST VSBY MENTIONED IN TAFS WILL BE 1 MI. THE NEXT ROUND OF -RA IS EXPECTED TO SPREAD ACROSS SOUTHWEST WI AROUND 06Z TONIGHT...MSN BY 08Z...AND EASTERN TAF SITES BY AROUND 09Z. THERE WILL BE A LULL IN PRECIP WED AFTERNOON AND WINDS WILL BEGIN TO RELAX A BIT. THEREFORE...CIGS AND VSBYS ARE EXPECTED TO STAY PRETTY LOW...IN THE IFR OR LOWER CATEGORY...FOR MUCH OF THE AFTERNOON. MARINE...DENSE FOG ADVY WILL CONTINUE FROM NORTH POINT LIGHT TO SHEBOYGAN UNTIL 00Z THIS EVENING. AS BOUNDARY LAYER WINDS CONT TO INCR...WOULD EXPECT SOME IMPROVEMENT IN VISIBILITY THIS EVENING. TIGHTENING PRES GRAD WL ALSO RESULT IN INCRG WINDS AND WAVES. PERSISTENT EASTERLY WINDS OF 10 TO 20 KTS WILL ALLOW WAVES TO APPROACH SMALL CRAFT ADVY LEVELS LATER TNGT INTO WED. DUE TO BORDERLINE SITUATION...WL CONTINUE TO HOLD OFF ON A SMALL CRAFT ADVY. SURGE OF HIGH LOW LEVEL RH LIKELY TO PRODUCE ADVECTION FOG ACROSS LAKE MI LATER WED AND WED NGT BTWN LOW PRES SYSTEMS. SECOND LOW PRESSURE SYSTEM EXPECTED TO AFFECT LAKE MI FROM WED NGT INTO THE WEEKEND WITH BACKING WNDS TO THE NORTH AND A TIGHTENING PRES GRAD PRODUCING PERIODS OF SMALL CRAFT ADVY CONDITIONS. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...DENSE FOG ADVISORY UNTIL 10 AM CST WEDNESDAY FOR LMZ643>645. && $$ SHORT/LONG TERM...DAVIS/REM AVIATION/MARINE...CRONCE