525 FXUS61 KCLE 302023 AFDCLE AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OH 323 PM EST TUE NOV 30 2010 .SYNOPSIS... A COLD FRONT WILL MOVE EAST ACROSS THE AREA THIS EVENING. THE COLD FRONT WILL USHER IN MUCH COLDER AIR TO THE REGION OVER THE NEXT SEVERAL DAYS. A TROUGH WILL MOVE EAST ACROSS THE AREA WEDNESDAY NIGHT. HIGH PRESSURE WILL BUILD EAST TOWARD THE AREA TOWARD THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... THE COLD FRONT WILL MOVE EAST ACROSS THE AREA THIS EVENING FORCING THE HEAVIER RAIN TO MOVE EAST OF THE AREA. HOWEVER...SOME GOOD UPPER LEVEL SUPPORT AND MOISTURE WILL KEEP THE THREAT OF PRECIPITATION GOING THROUGH THE NIGHT. AS COLDER AIR WORKS ITS WAY INTO THE REGION...THE PRECIPITATION WILL GRADUALLY BECOME MIXED WITH AND CHANGE OVER TO SNOW OVER THE WEST HALF OF THE AREA. A MIX OF RAIN AND SNOW CAN BE EXPECTED OVER THE EAST HALF WITH MAINLY RAIN OVER THE NORTHEAST LAKE SHORE REGION. WINDS HAVE ALREADY BEGUN TO SUBSIDE THIS AFTERNOON TO 10 TO 20 MPH ACROSS THE AREA. THEREFORE...WILL GO AHEAD AND DROP THE WIND ADVISORY AND HIGH WIND WARNING FOR EXTREME NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. TEMPERATURES DURING THE NIGHT WILL HANG IN THE LOWER 50S AHEAD OF THE COLD FRONT BUT WILL CONTINUE TO DROP THROUGH THE 40S INTO THE 30S FROM WEST TO EAST DURING THE NIGHT BEHIND THE COLD FRONT. && .SHORT TERM /6 AM WEDNESDAY THROUGH 6 AM WEDNESDAY/... ONCE THE COLDER AIR BECOMES FIRMLY ENTRENCHED OVER THE AREA...THE FLOW WILL BECOME WELL ALIGNED OUT OF 240 TO 260 DEGREES AND SET UP A LAKE EFFECT SNOW BAND ALONG THE NORTHEAST LAKE SHORE. THE BAND APPEARS IT COULD REMAIN PERSISTENT THROUGH THURSDAY NIGHT WHEN HIGH PRESSURE BUILDS NORTHEAST INTO THE REGION AND A TROUGH OF LOW PRESSURE SWEEPS SOUTHEAST ACROSS THE FORECAST AREA. THIS WILL TURN THE WINDS TO A MORE NORTHWESTERLY DIRECTION THURSDAY NIGHT INTO FRIDAY. DUE TO THE PERSISTENT FLOW EXPECTED...IT APPEARS THE COLD AIR ADVECTION WILL BE STRONG ENOUGH TO SUPPORT AT LEAST CONDITIONAL INSTABILITY BETWEEN THE AIR TEMPERATURE AND WATER TEMPERATURE. THERE IS A POSSIBILITY THAT SOME LOCATIONS IN THE HIGHER ELEVATIONS AWAY FROM THE LAKE COULD SEE SEVERAL INCHES OF SNOW ON THE GROUND BY FRIDAY. THE DURATION OF THE SNOW WILL BE A LONG DRAWN OUT ONE THAT CRITERIA FOR A LAKE EFFECT SNOW ADVISORY OR WARNING MAY NOT BE MET FOR DURATION. NEEDLESS TO DAY...WILL STILL HAVE TO MONITOR THE SITUATION FOR POSSIBLE WATCHES OR WARNINGS IN THE NEXT 24 HOURS. AT THIS TIME...CONFIDENCE IS NOT REAL HIGH ON WHEN AND WHERE THE LAKE EFFECT BAND WILL SET UP SO WILL HOLD OFF ON ISSUING A WATCH AT THIS TIME. A SERIES OF TROUGHS WILL ROTATE ACROSS THE ENTIRE FORECAST AREA TO BRING AT LEAST A CHANCE OF SNOW TO THE REST OF THE FORECAST AREA EACH PERIOD THROUGH THURSDAY. THREAT FOR THE EXTREME WEST AND SOUTH DIMINISHES BY THURSDAY NIGHT AND FRIDAY AS HIGH PRESSURE BUILDS TOWARD THE REGION. WE SHOULD SEE A SURGE OF REINFORCING COLD AIR THROUGH THIS PERIOD TO KEEP HIGH TEMPERATURES IN THE LOWER TO MIDDLE 30S TOMORROW AND LOWER 30S THURSDAY AND FRIDAY. THE COLD AIR ADVECTION WILL ALSO CAUSE LOW TEMPERATURES TO DIP INTO THE 20S EACH NIGHT. && .LONG TERM /WEDNESDAY THROUGH TUESDAY/... MODELS TRENDING EVEN WEAKER ON ENERGY THAT WOULD SUPPORT SOME SNOW ACROSS THE AREA ON SATURDAY. WITH THAT WENT WITH MAINLY SLIGHT CHANCE POPS ACROSS THE WESTERN HALF OF THE AREA AS WELL AS FOR SOME LINGERING LAKE EFFECT ACROSS NW PA. GOING INTO EARLY NEXT WEEK MODELS SHOWING LOW PRESSURE OVER NEW ENGLAND RETROGRADED WESTWARD BACK NORTH OF THE GREAT LAKES WITH CYCLONIC FLOW PERSISTING OVER THE REGION. GIVEN THE LITTLE CHANGE IN THE OVERALL PATTERN TOWARD THE END OF THE PERIOD MADE LITTLE CHANGES TO THE CURRENT FORECAST. NORTHERLY FLOW OVER LAKE ERIE WILL PERSIST PROVIDING AT LEAST THE CHANCE FOR SOME LAKE EFFECT SNOW SHOWERS ACROSS NE OH AND NW PA. TEMPERATURES IN THIS PATTERN WILL REMAIN MAINLY BELOW NORMAL. GUIDANCE TEMPS TRENDING WELL IN THE BELOW NORMAL DIRECTION SO SAW LITTLE REASON TO DEVIATE MUCH FROM A BLEND OF MEX/MOS TEMPS. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... COLD FRONT PUSHING INTO WESTERN OHIO THIS AFTERNOON AND WILL MAKE GRADUAL PROGRESS EASTWARD THROUGH EARLY TONIGHT. STRONGER LOW LEVEL WINDS CAUSING SOME WIND SHEAR EARLIER HAVE PUSHED OFF TO THE NORTHEAST EARLY THIS AFTERNOON SO REMOVED MENTION OF WIND SHEAR IN TAFS. SURFACE WINDS WILL CONTINUE TO BE GUSTY THIS AFTERNOON AND EVENING. SOME POCKETS OF VFR...BUT OTHERWISE MAINLY MVFR WITH SOME PERIODS OF IFR LIKELY AS THE COLD FRONT CROSSES SITES THIS AFTERNOON AND EVENING. WINDS SHIFTING TO THE SOUTHWEST BEHIND THE FRONT WITH MAINLY MVFR CIGS LINGERING THROUGH MUCH OF THE TAF PERIOD. THERE MAY BE SOME IMPROVEMENT DURING THE OVERNIGHT HOURS AS LOW PRESSURE MOVES WELL OFF TO THE NORTH OF THE REGION...BUT MVFR CIGS EXPECTED TO RETURN WEDNESDAY MORNING. .OUTLOOK...MVFR CEILINGS WEDNESDAY WITH SNOW SHOWERS MAINLY NE OH/NW PA. NON-VFR CONDITIONS ALSO POSSIBLE THURSDAY AND FRIDAY...ESPECIALLY NE OH/NW PA. && .MARINE... ENDED THE SMALL CRAFT ADVISORY FOR THE WEST END OF LAKE ERIE. WINDS HAVE DIMINISHED TO 10 TO 20 KNOTS...AND WITH A SOUTH TO SOUTHWEST FLOW WAVES WILL REMAIN BELOW 3 TO 5 FEET. COLD FRONT WILL PUSH ACROSS THE LAKE THIS EVENING. AS IT DOES THE WINDS WILL SHIFT TO THE SOUTHWEST. WILL BE A LITTLE LULL WITH THE WINDS...BUT AS THE COLD AIR MOVES OVER THE LAKE WINDS WILL PICK UP TO 15 TO 25 KNOTS AGAIN. AS A RESULT WILL NEED TO KEEP A SMALL CRAFT ADVISORY UP ON THE EASTERN PART OF THE LAKE. WITH LONG WAVE TROUGH REMAINING OVER THE LAKE...SMALL CRAFT ADVISORY WILL LIKELY BE NEEDED INTO THURSDAY NIGHT. THINGS FINALLY CALM DOWN ON FRIDAY AS HIGH PRESSURE BUILDS IN. MODELS STILL NOT IN GOOD AGREEMENT WITH THE STRENGTH AND TRACK OR EXACT TIMING OF THE NEXT SYSTEM. SO THERE REMAINS SOME UNCERTAINTY WITH THE WEEKEND FORECAST FOR THE WINDS AND WAVES ON LAKE ERIE. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EST THURSDAY FOR LEZ146>149. && $$ SYNOPSIS...LOMBARDY NEAR TERM...LOMBARDY SHORT TERM...LOMBARDY LONG TERM...ABE AVIATION...ABE MARINE...DJB