540 FXUS61 KBUF 270825 AFDBUF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BUFFALO NY 425 AM EDT SAT APR 27 2013 .SYNOPSIS... A WEAK UPPER LEVEL DISTURBANCE MOVING NORTH OF LAKE ONTARIO WILL BRING A PERIOD OF CLOUD COVER TODAY TO THE NORTH COUNTRY. OTHERWISE THE REST OF THE AREA WILL BE MOSTLY SUNNY AS HIGH PRESSURE REMAINS IN PLACE. THE NEXT CHANCE OF RAIN WILL ARRIVE SUNDAY NIGHT AND MONDAY AS A WEAK AREA OF LOW PRESSURE LIFTS OUT OF THE OHIO VALLEY. BUILDING WARMTH THIS WEEKEND WILL CONTINUE ALL OF NEXT WEEK WITH AN EXTENDED PERIOD OF ABOVE AVERAGE TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... SURFACE ANALYSIS EARLY THIS MORNING SHOWING HIGH PRESSURE IN PLACE FROM THE LOWER LAKES INTO NEW ENGLAND. WATER VAPOR IMAGERY AND OBJECTIVE RUC ANALYSIS SHOWING A WEAK SHORTWAVE CROSSING SOUTHERN QUEBEC AND SOUTHEAST ONTARIO...WITH AN ASSOCIATED BAND OF MID/HIGH CLOUDS. THIS FEATURE WILL CROSS THE NORTH COUNTRY THROUGH THE FIRST HALF OF TODAY WITH A PERIOD OF INCREASED CLOUD COVER. UPSTREAM RADARS DO SHOW A FEW WEAK BANDS OF SHOWERS OVER SOUTHERN ONTARIO... BUT SHORT TERM MODEL GUIDANCE SUGGESTS THE RAIN WILL FALL APART FOR THE MOST PART AS IT MOVES EAST INTO AN EVER DRIER AIRMASS AND INCREASING SUBSIDENCE. WITH THIS IN MIND WILL JUST CARRY SCATTERED SPRINKLES FOR THE NORTH COUNTRY FROM MID MORNING THROUGH MIDDAY WITH THE PASSAGE OF THE MID LEVEL TROUGH AND ASSOCIATED PERIOD OF WEAK ASCENT. FOR THE REST OF THE AREA...SOME HIGH CLOUDS ON THE SOUTHERN EDGE OF THIS SYSTEM WILL CLIP THE AREA...ESPECIALLY FROM THE THRUWAY NORTHWARD. THESE SHOULD REMAIN THIN ENOUGH TO STILL ALLOW FOR A GOOD AMOUNT OF SUNSHINE TO FILTER THROUGH. 850MB TEMPS RECOVER TO AROUND +5C TODAY...WHICH WILL SUPPORT HIGHS IN THE UPPER 60S IN MANY LOCATIONS WITH A FEW OF THE TYPICALLY WARMER SPOTS POSSIBLY REACHING 70. THE LIGHT SYNOPTIC FLOW COMBINED WITH STRONG DIFFERENTIAL HEATING WILL SUPPORT LOCAL LAKE BREEZES BY EARLY AFTERNOON WHICH WILL HOLD THE LAKESHORES IN THE 50S. TONIGHT HIGH PRESSURE WILL DRIFT OFF THE EASTERN SEABOARD...ALLOWING FOR ONGOING SOUTHERLY RETURN FLOW. THIS WILL KEEP TEMPS MILDER THAN RECENT NIGHTS...WITH MID TO UPPER 40S ON THE LAKE PLAINS AND LOWER 40S FARTHER INLAND. A FEW OF THE COLDER SOUTHERN TIER VALLEYS AND TUG HILL REGION WILL STILL DIP INTO THE UPPER 30S WHERE WINDS ARE MORE LIKELY TO DECOUPLE. ANY LEFTOVER MID/HIGH CLOUDS EAST OF LAKE ONTARIO ASSOCIATED WITH THE DEPARTING MID LEVEL SHORTWAVE SHOULD THIN OUT OVERNIGHT AS MID LEVEL HEIGHTS RISE AND SUBSIDENCE CONTINUES TO INCREASE. && .SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/... LOW PRESSURE LOCATED OVER THE SOUTHERN PLAINS EARLY THIS SATURDAY MORNING WILL LIFT TO THE NORTHEAST AND REACH THE OHIO VALLEY ON SUNDAY. HIGH PRESSURE ANCHORED OFF THE EAST COAST WILL KEEP OUR AREA DRY...BUT WARM AIR ADVECTION AHEAD OF THE APPROACHING SURFACE LOW WILL BRING A GRADUAL INCREASE IN CLOUDS TO WESTERN NEW YORK AND THE GENESEE VALLEY. THE SOUTHERLY FLOW BETWEEN THESE TWO SYSTEMS WILL ALLOW TEMPERATURES TO WARM WELL INTO THE 60S...AND MAYBE EVEN LOWER 70S ALONG THE LAKE PLAINS WHERE DOWNSLOPING WINDS WILL GIVE AN ADDED BOOST TO THE TEMPERATURES. AREAS EAST OF LAKE ONTARIO MAY ALSO WARM INTO THE LOWER 70S DUE TO MORE SUNSHINE. SUNDAY NIGHT AND MONDAY...THE WEAKENING SURFACE LOW WILL MOVE SLOWLY TO THE NORTH WHILE THE UPPER LEVEL TROUGH SHIFTS EAST ACROSS NEW YORK AND PA. A MODEST LOW LEVEL JET THAT WILL BE LIFTING NORTH ACROSS NEW YORK STATE WILL TAP INTO THE DEEPER MOISTURE THAT WILL BE IN PLACE OVER THE OHIO AND TENNESSEE VALLEYS. THIS WILL RESULT IN A GRADUAL SOUTH TO NORTH INCREASE TO LIKELY POPS DURING THIS PERIOD. IN TERMS OF QPF...THIS SYSTEM DOES NOT APPEAR AS IF IT WILL BE A BIG RAIN MAKER...BUT IT WILL KEEP OUR WEATHER A LITTLE UNSETTLED. THE INCREASE IN CLOUDS AND CHANCES FOR RAIN WILL KEEP TEMPERATURES A LITTLE COOLER ON MONDAY. THE SHOWERS WILL SHIFT SLOWLY TO THE EAST MONDAY NIGHT AND TUESDAY AS THE UPPER TROUGH HEADS EAST TO THE NEW ENGLAND COAST. BASED ON THIS TREND...EXPECT ANY LINGERING SHOWERS TO BE EAST OF OUR CWA BY NOONTIME TUESDAY. THE PERSISTENT SOUTHERLY FLOW AND ANTICIPATED TREND TOWARD SOME INCREASE IN SUNSHINE WILL ALLOW TEMPERATURES TO WARM WELL INTO THE 60S AGAIN ON TUESDAY. DRY WEATHER AND SEASONABLY MILD TEMPERATURES WILL CONTINUE THROUGH TUESDAY NIGHT. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... AN UPPER LEVEL TROUGH WILL DIG INTO THE NATIONS MIDSECTION DURING THE MIDDLE OF THE WEEK...WHILE A RIDGE REMAINS IN PLACE FROM THE MIDDLE ATLANTIC STATES TO THE CANADIAN MARITIMES. THE UPPER TROUGH IS FORECAST TO DEEPEN FURTHER AND TRANSITION TO A CUTOFF LOW OVER THE MID MISSISSIPPI VALLEY BY FRIDAY. THE DEEPENING TROUGH WILL HELP TO MAINTAIN A DOWNSTREAM RIDGE OVER THE NORTHEAST AND NEW ENGLAND. THE UPPER RIDGE SHOULD HELP TO KEEP THE STEADIER PCPN...ASSOCIATED WITH THE UPSTREAM TROUGH...TO OUR WEST. THE DEEP LAYERED SOUTHERLY FLOW WILL KEEP TEMPERATURES MILD THROUGH THURSDAY. THICKENING CLOUDS AND SOME INCREASE IN CHANCE FOR SHOWERS MAY KEEP TEMPERATURES A LITTLE COOLER ON FRIDAY. HOWEVER...IF THE THE ECMWF'S UPPER LEVEL CONFIGURATION (WHICH FEATURES A STRONGER AND MORE PERSISTENT UPPER LEVEL RIDGE OVER THE NORTHEAST) VERIFIES...THEN MILDER AND DRY CONDITIONS MAY LINGER INTO FRIDAY. && .AVIATION /09Z SATURDAY THROUGH WEDNESDAY/... VFR WILL PREVAIL FOR THE 06Z TAF CYCLE. IR SATELLITE IMAGERY SHOWING MAINLY CLEAR SKIES EARLY THIS MORNING...WITH JUST SOME THIN/HIGH CIRRUS BEGINNING TO INCREASE. THESE CLOUDS WILL THICKEN AND LOWER INTO A MID LEVEL DECK BY SATURDAY MORNING ACROSS THE NORTH COUNTRY INCLUDING KART. THIS AREA MAY EVEN SEE A FEW SPRINKLES OR VERY LIGHT SHOWERS THROUGH THE FIRST HALF OF SATURDAY...BUT THESE WILL REMAIN LIGHT ENOUGH TO KEEP VSBY VFR. OTHERWISE THE REST OF THE AREA WILL JUST SEE SCT CIRRUS LEVEL CLOUDINESS. THE LIGHT BACKGROUND WINDS WILL ALLOW LOCAL LAKE BREEZES TO DEVELOP DURING THE AFTERNOON WITH WIND SHIFTS LIKELY OCCURRING WITHIN 10-20 MILES OF THE LAKESHORES. OUTLOOK... SUNDAY AND SUNDAY NIGHT...MOSTLY VFR WITH SHOWERS LIKELY DEVELOPING SUNDAY AFTERNOON AND NIGHT. MONDAY...MOSTLY VFR WITH A CHANCE OF SHOWERS. TUESDAY THROUGH WEDNESDAY...VFR. && .MARINE... HIGH PRESSURE IN PLACE FROM THE OHIO VALLEY TO THE NORTHEAST WILL PROVIDE LIGHT WINDS TODAY AND TONIGHT. STRONG DIFFERENTIAL HEATING TODAY WILL SUPPORT LAKE BREEZE DEVELOPMENT BY EARLY AFTERNOON WITH WINDS BECOMING LOCALLY ONSHORE ON BOTH LAKES ERIE AND ONTARIO. BY SUNDAY NIGHT AND MONDAY HIGH PRESSURE WILL DRIFT OFF THE EAST COAST. THIS WILL ALLOW THE PRESSURE GRADIENT TO INCREASE SOMEWHAT...WITH SOUTH TO SOUTHEAST WINDS INCREASING BUT STILL REMAINING WELL BELOW SMALL CRAFT ADVISORY CRITERIA. SOUTH TO SOUTHEAST WINDS WILL REMAIN IN PLACE MUCH OF NEXT WEEK WITH GENERALLY LIGHT WAVE ACTION GIVEN THE OFFSHORE FLOW. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...HITCHCOCK NEAR TERM...HITCHCOCK SHORT TERM...TJP LONG TERM...TJP AVIATION...HITCHCOCK MARINE...HITCHCOCK