FXUS61 KBUF 241931 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 330 PM EDT TUE AUG 24 2004 .SHORT TERM (TONIGHT THROUGH FRIDAY)... BAND OF LOW LEVEL MOISTURE ALONG WASHED OUT COLD FRONT OVER THE SOUTHERN TIER WILL CONTINUE TO MIX OUT THROUGH THE REST OF THE DAYLIGHT HOURS. DIURNAL SC/CU WILL DISSIPATE TONIGHT WITH AREAS OF FOG REFORMING IN THE SOUTHERN TIER VALLEYS. MODELS ARE IN AGREEMENT THAT A RESURGENCE OF MOISTURE AND CLOUDS WILL APPROACH FROM THE WEST ON WEDNESDAY. ETA INITIALIZED WELL ON THE CONVECTION OVER SOUTHWESTERN OHIO THIS AFTERNOON WHICH THEN DEPICTS SHRA/TSRA OVER WESTERN NY ON WED AFTERNOON. WENT WITH CHANCE POPS CLOSER TO FWC/MAV POPS RATHER THAN THE HIGHER LIKELY POPS AS IN MET MOS. HIGH PRESSURE BUILDING OVER THE WESTERN ATLANTIC WILL BLOCK THE EASTWARD PROGRESSION OF TROUGHING OVER THE MID CONTINENT...BUT A FEW WEAK VORTS IN THE SOUTHWESTERLY FLOW ALOFT WILL KEEP CHANCE POPS FOR THURSDAY AFTERNOON. DEEPENING MOISTURE THROUGH THE WEEK ON THE PERSISTENT SOUTHWESTERLY FLOW WILL MAKE CONDITIONS MORE HUMID AND PRONE TO CONVECTION ALONG LAKE BREEZE BOUNDARIES. I STUCK WITH THE LAKE ERIE BREEZE AS THE MORE LIKELY AREA FOR CONVECTION AS THE LAKE ONTARIO BREEZE CONVERGENCE WILL BE SOMEWHAT SUPPRESSED BY THE BUILDING HIGH PRESSURE IN THE EAST. && .LONG TERM (FRIDAY NIGHT THROUGH TUESDAY)... AS THE WESTERN ATLANTIC RIDGE STRENGTHENS AND BUILDS WESTWARD OVER THE SOUTHEASTERN U.S. THERE WILL BE AS EASTWARD SHIFT OF THE MID CONTINENT TROUGH. THIS WILL LEAD TO A FLATTENING OF THE RIDGE AND INCURSIONS OF COOLER AIR OVER THE GREAT LAKES. A WEAK COLD FRONT SWINGS THROUGH ON FRIDAY NIGHT AND SATURDAY MORNING WITH CHANCE POPS FOR SHRA/TSRA...THEN THE FRONT STALLS JUST SOUTH OF THE FORECAST AREA OVER CENTRAL PA. RETURNING WARM H8 ADVECTION BRINGS PRECIP BACK TO THE REGION ON SUNDAY AFTERNOON THROUGH MONDAY AS THE WARM FRONT REMAINS TO THE SOUTH OF REGION. ANOTHER COLD FRONT DROPS BY ON TUESDAY....CHANCE POPS CONTINUE. && .AVIATION... PLENTY OF LOW LEVEL MOISTURE ACROSS THE SOUTHERN TIER OF NEW YORK WILL CONTINUE TO PRODUCE MVFR CIGS AT TIMES THROUGH LATE AFTERNOON BEFORE DIURNAL HEATING CEASES AND CIGS DISSIPATE. THE REST OF THE REGION WILL BE VFR THROUGH TONIGHT. HOWEVER, ACROSS THE SOUTHERN TIER WE WILL LIKELY SEE A RETURN OF FOG TONIGHT WHICH WILL LOWER CIGS/VSBYS TO IFR AT TIMES IN PLACES SUCH AS JHW. THE ONLY FLY IN THE OINTMENT WITH FOG TONIGHT WILL BE THE FORECAST WIND SPEEDS JUST ABOVE THE SURFACE. BUFKIT ETA PROFILE FORECAST SOUNDINGS FOR TONIGHT SUGGEST 25KT+ WINDS AT 1500 FT. EVEN THOUGH THE SURFACE WILL BE MAINLY DECOUPLED FROM THOSE WINDS...THEY MAY MIX DOWN ENOUGH TO STIR UP CONDITIONS AT TIMES. BASED ON THE UPS FOG ALGORITHM FOR JHW, THE POTENTIAL MIXING COULD LIMIT SURFACE FOG AND JUST KEEP A LOW STRATUS DECK ACROSS THAT REGION. JHW IS AT AN ELEVATION OF 1700 FT. SO IN ANY EVENT, WE WOULD LIKELY SEE IFR CIGS AND COULD EVEN BE IFR FOR VSBY IF STRATUS IS THAT LOW. ON WEDNESDAY WE SHOULD STAY IFR FROM GENESEE VALLEY EASTWARD. THERE IS THE POTENTIAL BY LATE MORNING HOWEVER TO SEE MVFR CIGS AT TIMES IN ISOLATED SHOWERS THAT COULD DEVELOP BY LATE MORNING. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY IN EFFECT THIS EVENING LAKE ONTARIO FROM THE NIAGARA RIVER TO SODUS BAY. $$ SHORT/LONG TERM...HIBBERT AVIATION...NIZIOL