990 FXUS61 KBGM 311140 AFDBGM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BINGHAMTON NY 640 AM EST TUE DEC 31 2013 .SYNOPSIS... WEAK LOW PRESSURE TRACKING ACROSS NEARBY SOUTHERN CANADA WILL BRING SOME LIGHT SNOW TO THE AREA. SIGNIFICANT LAKE EFFECT SNOW WILL DEVELOP LATE THIS AFTERNOON THROUGH EARLY WEDNESDAY MORNING OVER NORTHERN ONEIDA COUNTY. MORE WIDESPREAD SNOW IS EXPECTED WEDNESDAY NIGHT THROUGH THURSDAY NIGHT, WITH THE POTENTIAL FOR MODERATE ACCUMULATIONS. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AT 445 AM...SFC LOW PRES WAS LOCATED OVER GEORGIAN BAY AS HIGH PRESSURE OVER NORTHERN NYS SLIDES EAST INTO THE CANADIAN MARITIMES. THIS WEAK LOW PRES WILL MOVE EAST ACROSS NEARBY SOUTHERN CANADA BRINGING MUCH OF THE AREA SOME LIGHT SNOW FROM MID MORNING THROUGH EARLY AFTERNOON. SNOWFALL WILL BE LIGHT, GENERALLY AROUND ONE INCH ACROSS THE NRN CWA, LESS THAN AN INCH IN THE SOUTHERN TIER AND A FEW TENTHS ACROSS NE PA. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... TONIGHT...BEHIND THIS WEAK WAVE LOW LEVEL FLOW BECOMES VERY FAVORABLE FOR LES ACROSS NRN ONEIDA COUNTY. MODELS LAST NIGHT WERE INDICATING THE POTENTIAL FOR THE BAND TO DROP SOUTH ACROSS ONONDAGA, MADISON AND SOUTHERN ONEIDA COUNTY BUT THE LATEST SUITE KEEPS THE BAND ACROSS THE NRN PTN OF ONEIDA COUNTY THROUGH THE OVERNIGHT PERIOD THEN LIFTS IT NORTH WED MORNING. LONG FETCH, DEEP LAYER OF INSTABILITY AND SNOW RATIOS OF 25/1 WILL RESULT IN SNOW ACCUMS OF 10 TO 15 INCHES ESPECIALLY IN THE NORTHWEST CORNER OF THE COUNTY. A LAKE ERIE BAND MAY BRING SOME LIGHT ACCUM ACROSS THE SOUTHERN TIER AND NORTHERN TIER OF PA WITH ACCUMS AROUND ONE INCH LIKELY. WEDNESDAY THROUGH THURSDAY NIGHT...AN UPPER LEVEL TROF WILL TRACK FROM THE MID WEST EAST ACROSS THE OH/TN VALLEYS THEN OFF THE EAST COAST. THE ASSOCIATED SFC LOW WILL TRACK SOUTH OF THE AREA WITH STRONG HIGH PRES CENTERED OVER EASTERN CANADA. AREA WILL RESIDE IN A STRONG BAROCLINIC ZONE WITH PROLONGED ISENTROPIC LIFT AS FEATURE TRACKS FROM THE MID WEST ACROSS THE OHIO VALLEY TO THE DELMARVA REGION. ATTM MODELS CONTINUE TO SHOW GULF MOISTURE NOT REACHING THE AREA. LIGHT SNOW WILL SPREAD OVER THE REGION WED AFTERNOON AND CONTINUE THROUGH THURSDAY NIGHT. THIS LOOKS TO BE A PROLONGED PERIOD OF LIGHT SNOW WITH MODERATE ACCUMS LIKELY. ARCTIC HIGH PRES OVER EASTERN CANADA WILL PROVIDE PLENTY OF COLD AIR AND HIGH SNOW RATIOS. && .LONG TERM /FRIDAY THROUGH MONDAY/... 3 PM MON UPDATE... SYNOPTIC SNOWFALL EVENT SHOULD BE ONGOING THU NGT...PERHAPS LINGERING INTO FRI. THERE ARE STILL PLENTY OF MODEL DISCREPANCIES WITH THIS STORM...AS THE 12Z EC REMAINS THE MOST AMPLIFIED AND SLOWEST WITH THE MAIN UPPER-LVL TROUGH AXIS...WHILE THE GFS/CAN GEM ARE MORE PROGRESSIVE. ATTM...WPC IS LEANING TWDS THE MORE PROGRESSIVE SOLNS...GIVEN THE PROGGED CANADIAN MARITIME UPPER-LVL LOW...AND THE CONFLUENT PATN UNDERNEATH IT...WHICH SEEMS REASONABLE AT THIS EARLY VANTAGE PT. EVEN SO...NICE WAA/FGEN FORCING INTO THU NGT...FOLLOWED BY BRIEF DEFORMATION BAND MECHANICS INTO EARLY FRI...LIKELY TRANSLATES TO AT LEAST WIDESPREAD ADVSY LVL SNOW ACCUMS. STAY TUNED...AS MANY DETAILS ARE YET BE IRONED OUT. THE OTHER MAIN STORY THIS PD IS THE ARCTIC AMS EXPECTED TO PLUNGE SWD INTO CNY/NE PA FRI INTO SAT. IF ANYTHING...THE MODELS HAVE TRENDED EVEN COLDER IN RECENT RUNS...WITH BOTH THE GFS/EC SHOWING TEMPS NOT MUCH ABV ZERO FRI...THEN WELL BLO ZERO FRI NGT/EARLY SAT. WE'VE BEEN ADVERTISING SINGLE DIGIT HIGHS ON FRI...WITH WELL BLO ZERO READINGS FRI NGT/SAT MRNG...SO WE DIDN'T MAKE MANY CHGS HERE. WE DID NUDGE TEMPS LWR LTR IN THE WEEKEND INTO EARLY NEXT WEEK...TO BETTER MATCH THE LATEST STATISTICAL GUIDANCE. MAINLY DRY WX IS STILL FORESEEN AT THE BEGINNING OF THE WEEKEND...WHEN THE DEEPEST COLD WILL LIKELY BE IN PLACE. FROM SUN INTO EARLY NEXT WEEK...ADDITIONAL NRN STREAM SHRT WV/FRNTL PASSAGES ARE LIKELY...SO WE'VE JUST GONE WITH A GENERIC CHC OF SHSN/FLRYS FOR NOW. AS WE DRAW CLOSER IN TIME...HOPEFULLY WE'LL GET A BETTER FEEL FOR WHERE THE MOST PERSISTENT LES BANDS MAY SET UP. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... 12Z UPDATE... PERIODS OF LIGHT SNOW WILL OVERSPREAD THE AREA THIS MORNING WITH SNOW SHOWERS PERSISTING INTO THE AFTERNOON. CONDITIONS IN LIGHT SNOW WILL FEATURE MOSTLY MVFR CIGS AND VSBYS WITH BRIEF PERIODS OF IFR VSBYS IN HEAVIER SNOW SHOWERS. LAKE EFFECT SNOW WILL DEVELOP ALONG OR NORTH OF THE THRUWAY LATE THIS AFTERNOON AND CONTINUE TONIGHT POSSIBLY BRINGING SOME HEAVY SNOW TO THE RME TAF SITE... OTHERWISE MAINLY DRY WEATHER CAN BE EXPECTED ELSEWHERE TONIGHT WITH MVFR CIGS AND VFR VSBYS. WINDS WILL INCREASE FROM THE WEST-SOUTHWEST AT 10 TO 15 KTS THIS AFTERNOON WITH A FEW GUSTS TO 20 KTS. WEST WINDS WILL DECREASE TO 10 KTS OR LESS LATE TONIGHT. OUTLOOK... WED...MVFR/IFR SHSN IN KSYR/KRME...WITH MAINLY VFR ELSEWHERE. WED NGT-THU NGT...IFR SNOW LIKELY AREA-WIDE. FRI...LINGERING RESTRICTIONS PSBL IN SHSN. FRI NGT/SAT...MAINLY VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...LAKE EFFECT SNOW WARNING FROM 4 PM THIS AFTERNOON TO 10 AM EST WEDNESDAY FOR NYZ009. && $$ SYNOPSIS...RRM NEAR TERM...RRM SHORT TERM...RRM LONG TERM...MLJ AVIATION...MSE/PVN