FXUS61 KCLE 010741 AFDCLE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OH 341 AM EDT SUN AUG 1 2010 .SYNOPSIS... A WEAK AREA OF LOW PRESSURE WILL BE OVER THE OHIO VALLEY TODAY AND THEN IT WILL WEAKEN TONIGHT. A HIGH PRESSURE RIDGE WILL BUILD OVER THE REGION TONIGHT AND LAST INTO EARLY TUESDAY. THE NEXT COLD FRONT IS EXPECTED TO MOVE INTO THE REGION WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH TEMPERATURE AND DEW POINT SPREAD LOW AT MANY LOCATIONS...DECREASING CLOUDS AND LIGHT WINDS...WENT PATCHY FOG OR PATCHY DENSE OVER THE WEST TWO THIRDS OF THE FORECAST AREA THROUGH 13Z. HIGH PRESSURE RIDGE TO THE NORTH WILL BE SINKING SOUTH TODAY AND THE INVERTED TROF WILL BE NOSING INTO EXTREME EASTERN OHIO AND NORTHWEST PA. THE NAM IS DRY WITH THIS FEATURE WHILE THE OTHER MODELS ARE NOT...THIS INCLUDES THE SREF...ECMWF AND GFS. THE LOCAL NAM MODEL TRIES TO FORECAST SOME QPF THIS AFTERNOON IN THE EAST. WITH THE AIR MASS A LITTLE UNSTABLE AND THE CONVECTIVE TEMPERATURE IN THE LOWER TO MID 80S AND FORECAST HIGHS IN THE MID 80S...A THREAT IS THERE...30 POPS IN THE EXTREME EAST. MOS GUIDANCE GENERALLY CLOSE ON THE HIGHS WENT WITH THE WARMER GFS MOS GUIDANCE BASED ON WHAT HAPPENED UPSTREAM SATURDAY AND A LOCAL SCHEME. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... A THREAT OF SHOWERS AND THUNDERSTORMS COULD LINGER IN THE EXTREME EAST EARLY THIS EVENING THEN JUST SOME CLOUDS ACROSS THE FORECAST AREA. HIGH PRESSURE RIDGE ACROSS THE REGION MONDAY. DIDN'T MAKE TOO MANY CHANGES TO THE TUESDAY THROUGH WEDNESDAY NIGHT PORTION OF THE FORECAST. MODELS IN GENERAL AGREEMENT IN HINTING AT A PREFRONTAL TROUGH FOR TUESDAY AND THEN A BETTER CHANCE OF QPF TUESDAY NIGHT AND WEDNESDAY AS THE FRONT MOVES THROUGH AND WAVES MOVE ALONG IT. MOS GUIDANCE TEMPERATURES ARE CLOSE EXCEPT FOR TUESDAY. WENT CLOSE TO THE GUIDANCE FOR THE MOST PART. ON TUESDAY LEANED MORE TOWARD THE WARMER MOS GFS BASED ON EXPECTING SOME SUNSHINE AND JUST A LOW CHANCE POP. && .LONG TERM /THURSDAY THROUGH SATURDAY/... THIS RUN OF THE MODELS IS TRYING TO INDICATE A WAVE DEVELOPING ALONG THE FRONT AND A THREAT OF SHOWERS AND THUNDERSTORMS. AT THIS TIME JUST WENT WITH 20 POPS UNTIL CONDITIONS BECOMES CLEARER. THE GFS TRIES TO INDICATE DRY FOR FRIDAY WHILE THE ECMWF DOES NOT AS IT HAS THE BOUNDARY CLOSE TO THE FORECAST AREA. AT THIS TIME KEPT IT DRY UNTIL IT BECOMES CLEARER. HIGH PRESSURE RIDGE IS EXPECTED FOR SATURDAY...THIS SEEMS REASONABLE. MEX TEMPERATURES ARE VERY WARM...WENT JUST A LITTLE COOLER AND DIDN'T MAKE SIGNIFICANT CHANGES FROM PREVIOUS FORECAST. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... UPPER TROUGH OVER THE AREA WILL MOVE EAST BY DAWN AND HIGH PRESSURE AT THE SURFACE AND ALOFT WILL BUILD INTO THE AREA FROM THE WEST DURING THE DAY. WILL LIKELY SEE SCATTERED MVFR VISIBILITIES AROUND DAWN IN EARLY MORNING HAZE/FOG. THIS SHOULD END BY 13-14Z. EXPECT CUMULUS TO DEVELOP IN THE AFTERNOON AT 4 TO 5 KFT. BEST CHANCE FOR A BROKEN DECK WOULD BE YNG AND CAK BUT FOLLOWING THE NAM MOISTURE...OTHER AREAS SHOULD REMAIN PRIMARILY SCATTERED. .OUTLOOK...SCT MVFR/IFR POSSIBLE TUESDAY EVENING INTO WEDNESDAY IN THUNDERSTORMS. ALSO MORNING MIST/FOG COULD BRING CONDITIONS BRIEFLY TO MVFR DURING THE EARLY MORNING HOURS DURING THE PERIOD. && .MARINE... LOW PRESSURE OVER THE LOWER OHIO VALLEY WILL EXTEND A TROUGH OF LOW PRESSURE NORTHEAST INTO EASTERN OHIO OR WESTERN PA TODAY. MOISTURE AND INSTABILITY ON THE EAST SIDE OF THIS TROUGH COULD ALLOW FOR A FEW SHOWERS OR THUNDERSTORMS ON THE EASTERN THIRD OF THE LAKE TODAY. HIGH PRESSURE HOWEVER WILL ALSO BE BUILDING TOWARD THE LAKE FROM THE WEST AND BY EVENING SHOULD BE OVER THE LAKE. BETWEEN THESE TWO SYSTEMS AN EAST TO NORTHEAST FLOW WILL OCCUR OVER THE LAKE TODAY. THIS WILL CHURN WAVES MAINLY ON THE CENTRAL AND WEST THIRDS. WILL HAVE WAVES 1 TO 3 FEET WEST AND 2 FEET OR LESS EAST. WAVES MOSTLY 2 FEET OR LESS THROUGH THE PERIOD ALTHOUGH COULD SEE 2 TO 3 FEET WEDNESDAY WITH THE COLD FRONT. HIGH PRESSURE WILL MOVE TO THE EAST COAST TUESDAY AND ALLOW WINDS TO TURN SOUTH TO SOUTHWEST. WEDNESDAY A COLD FRONT WILL CROSS THE LAKE FROM THE NORTHWEST AFTER DAYBREAK. SOUTHWEST WINDS AHEAD OF THE BOUNDARY WILL TURN WESTERLY POST FRONT. THURSDAY AND FRIDAY THE FRONT WILL SLOW THEN STALL ACROSS CENTRAL OR SOUTHERN OHIO. WEAK HIGH PRESSURE WILL BUILD IN ACROSS THE LAKE FROM THE WEST. BEST CHANCE FOR THUNDERSTORMS WILL BE TUESDAY...AHEAD OF THE COLD FRONT...AND WEDNESDAY WITH THE COLD FRONT. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KIELTYKA NEAR TERM...KIELTYKA SHORT TERM...KIELTYKA LONG TERM...KIELTYKA AVIATION...TK MARINE...TK