862
FXUS61 KBGM 260552
AFDBGM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
1252 AM EST FRI DEC 26 2025
WHAT HAS CHANGED
19Z NBM DATA, ALONG WITH THE INCOMING CAMS ARE COMING INTO
BETTER AGREEMENT WITH WHERE THE MIX WITH SLEET WILL OCCUR AND
WHERE THE HEAVIEST SNOW WILL LIKELY OCCUR WITH THIS UPCOMING
SYSTEM. THE LATEST FORECAST INCORPORATES 19Z NBM AND 12Z WPC QPF
GUIDANCE, ALONG WITH THE LATEST WEATHER TYPE GRIDS FROM NBM.
MINOR CHANGES TO WHERE THE MIX WITH SLEET WILL OCCUR, WITH MOST
GUIDANCE NOW BRINGING THE SLEET AS FAR EAST-NORTHEAST AS ABOUT
BINGHAMTON FOR A FEW HOURS FRIDAY EVENING. THERE WILL BE MORE
SLEET ACROSS THE CENTRAL SOUTHERN TIER AND THE WYOMING VALLEY
REGION OF NE PA. THIS IS WHERE SNOW/SLEET AMOUNTS ARE STILL
EXPECTED TO DROP OFF RAPIDLY, WITH JUST 1 TO 3 INCHES.
THE ONE MORE SIGNIFICANT CHANGE WITH THIS EVENINGS UPDATE WAS
TO INCREASE EXPECTED SNOWFALL ACROSS ONONDAGA, CORTLAND,
CHENANGO, OTSEGO AND SOUTHERN ONEIDA COUNTIES WHERE HIGHER QPF
AND SLRS ARE NOW EXPECTED (AND MUCH LOWER CHANCE FOR ANY SLEET
TO MIX IN AND CUT DOWN ON TOTALS). 19Z NBM GIVES 50-80% CHANCE
TO EXCEED 7 INCHES OF SNOW NOW IN THESE COUNTIES. TRENDS WILL
BE WATCHED CLOSELY IN THIS AREA WITH THE INCOMING 00Z GUIDANCE.
WARNINGS AND ADVISORIES REMAIN UNCHANGED WITH THIS UPDATE.
KEY MESSAGES
1) STRONG CLIPPER SYSTEM BRINGING WIDESPREAD SNOW AND SOME
MIXED PRECIPITATION TO THE REGION FRIDAY MID DAY INTO SATURDAY
MORNING.
2) GREAT LAKES LOW BRINGS THREAT OF SOME ISOLATED POCKETS OF
FREEZING RAIN SUNDAY NIGHT PRIOR TO CHANGING TO RAIN MONDAY WITH
GUSTY WINDS.
3) COLD WEATHER RETURNS LATE MONDAY THROUGH THE REST OF THE
WEEK WITH PERSISTENT LAKE EFFECT SNOW.
DISCUSSION
KEY MESSAGE 1...
A FAIRLY POTENT CLIPPER SYSTEM MOVES THROUGH THE NORTHEAST
TOMORROW INTO TOMORROW NIGHT. STRONG WARM AIR ADVECTION WILL
LEAD TO GOOD ISENTROPIC LIFT WITH A NARROW CORRIDOR OF HEAVIER
SNOW. THERE IS STILL A GOOD AMOUNT OF UNCERTAINTY WHERE THIS
HEAVIER BAND OF SNOW WILL SET UP. THIS MORNINGS MODEL RUNS WITH
THE HRRR ESPECIALLY LOOK TO BE WAY TO BULLISH ON SNOWFALL ACROSS
NEPA INTO THE SOUTHERN TIER. FORECAST SOUNDINGS AND VERTICAL
CROSS SECTIONS ACROSS THE WARM FRONT SHOW A 700 MB WARM LAYER.
THE HRRR HAS A LACK OF VERTICAL LAYERS SO LIKELY THE 700 MB WARM
LAYER IS UNDERDONE WHILE IN THE NAM, THE WARM NOSE IS LIKELY
BEING OVERDONE. THE HEAVIER PRECIPITATION IN THE FGEN BAND MAY
BE ABLE TO KEEP THE LAYER BELOW FREEZING ON THE NORTHERN FRINGE
OF THE WARM NOSE. ANOTHER ISSUE WITH THE MODELS IN REGARDS TO
ITS SNOWFALL AMOUNTS IS HOW HIGH THE DGZ IS. CROSS SECTIONS SHOW
THAT THE LIFT THROUGH THE DGZ IS MAXIMIZED A LITTLE FARTHER
NORTH THAN WHERE THE HIGHEST QPF IS SO WOULD NOT BE SURPRISED IF
THE SNOW BAND ENDS UP BEING ABOUT 20 TO 30 MILES NORTH OF THE
NORTHERN EXTENT OF THE SLEET RATHER THAN JUST NORTH OF THE MIX
LINE. WARNING CRITERIA SNOW WILL BE POSSIBLE UNDER THIS BAND AND
WITH HOW NARROW IT IS, GUESSING WHERE IT WILL BE TO ISSUE
WARNINGS WILL BE TOUGH SO WARNINGS ACROSS CNY, AND PERHAPS MORE
OF NEPA IF THE BAND ENDS UP BEING WELL SOUTH, MAY BE ISSUED WITH
SHORT NOTICE.
SNOW FOR THE SOUTHERN TIER AND NORTH WAS INCREASED, WITH THE
COUPLED RIGHT ENTRANCE REGION AND THE LIFT EXIT REGION OF TWO
JET MAXES WITH LIFT BEING FAIRLY BROAD. FOR THE WESTERN SOUTHERN
TIER AND WESTERN NEPA, WARM AIR LOOKS TO WIN OUT WITH SLEET
MIXING IN SO THE TIME OF ALL SNOW MAY ONLY BE A FEW HOURS BEFORE
CHANGING OVER TO SLEET. FREEZING RAIN THREAT CONTINUES TO
DWINDLE AS THE DEPTH OF COLD AIR BELOW THE WARM LAYER IS DEEP
AND ANYTHING THAT MELTS WILL REFREEZE. HOW FAR NORTH THIS MIXED
LAYER WILL GET IS CRITICAL FOR WHERE THE HEAVIEST SNOW FALLS.
CURRENT SNOW MAP DOES NOT HAVE AS SHARP OF A GRADIENT AS THERE
WILL LIKELY BE AND AS WE GET CLOSER TO THE EVENT, WE WILL BE
ABLE TO REFINE WHERE THAT MIXING LINE MAY GET TO. RIGHT NOW,
HIGHEST CONFIDENCE IN WHERE HEAVIEST SNOW WILL BE IS IN THE
CATSKILLS WHERE THERE IS BETTER MOISTURE IN PLACE AND WITH THE
HELP OF TERRAIN, SNOW AMOUNTS LOOK TO BE NEAR AND ABOVE WARNING
CRITERIA.
KEY MESSAGE 2...
A STRONG LOW MOVES INTO THE GREAT LAKES REGION SUNDAY NIGHT
INTO MONDAY WITH WARM AIR ADVECTION THROUGH NY AND PA. 850 MB
TEMPERATURES RISE ABOVE FREEZING WELL PRIOR TO PRECIPITATION
ONSET LATE SUNDAY INTO SUNDAY NIGHT. GIVEN THE TIMING,
TEMPERATURES DURING THE DAY SUNDAY SHOULD RISE ABOVE FREEZING
FOR MOST OF THE AREA BUT DEEPER, SHELTERED VALLEYS IN THE
CATSKILLS UP INTO THE TUG HILL MAY HOLD ON TO BELOW FREEZING
TEMPERATURES. POCKETS OF FREEZING RAIN WAS KEPT IN THE GRIDS FOR
SE FACING VALLEYS IN THE CATSKILLS AS THOSE VALLEYS WILL BE
SHELTERED THE BEST AND MAINTAIN FREEZING TEMPERATURES LONGER
WITH THE SW FLOW ALOFT. BY MONDAY MORNING, WITH 850 MB TEMPS
APPROACHING 10C, IT WILL BE TOUGH TO MAINTAIN ANY BELOW FREEZING
SURFACE TEMPERATURES SO RAIN WILL BE THE DOMINANT PRECIP TYPE.
WINDS WILL ONCE AGAIN BE GUSTY WITH THE STRONG WARM AIR
ADVECTION BUT AS TYPICAL THIS TIME OF THE YEAR, A STABLE LAYER
BELOW THE WINDS WILL PREVENT STRONGER WINDS FROM MIXING DOWN.
A STRONG COLD FRONT MOVES THROUGH MONDAY AFTERNOON/NIGHT
BRINGING A QUICK DROP IN TEMPERATURE AND A BRIEF TRANSITION FROM
RAIN TO SNOW BEFORE COLDER, DRIER AIR BRINGS AN END OF THE
PRECIPITATION OUTSIDE OF THE LAKE EFFECT AREAS. 850 MB WINDS ON
THE BACK SIDE OF THE LOW GET UP OVER 50 KNOTS SO THERE IS A
CHANCE THAT WIND ADVISORIES MAY BE NEEDED WITH STEEP LOW LEVEL
LAPSE RATES AND EFFICIENT DOWNWARD MOMENTUM TRANSFER.
KEY MESSAGE 3...
MONDAY NIGHT INTO NEXT WEEK LOOKS FAVORABLE FOR PERSISTENT LAKE
EFFECT SNOW. A STACKED LOW FORMS SOUTH OF THE HUDSON BAY WHICH
IS CLIMATOLOGY A FAVORABLE LOCATION FOR LONG LIVED LAKE EFFECT
EVENTS. 850 MB WINDS ARE MOSTLY WESTERLY AND MEAN WINDS IN
ENSEMBLES HINT AT A MULTI-LAKE CONNECTION, WHILE MEAN
TEMPERATURES REMAIN AT OR BELOW -10C. IT IS TOO FAR OUT TO
REALLY FIGURE OUT BAND ORGANIZATION OR ORIENTATION BUT SOMETHING
TO WATCH OVER THE NEXT FEW DAYS.
AVIATION /06Z FRIDAY THROUGH TUESDAY/
MAINLY VFR CONDITIONS ARE EXPECTED TO CONTINUE FOR THE TIME
BEING; AT LEAST THROUGH THIS MORNING AND LIKELY INTO THE EARLY
AFTERNOON AS WELL. AFTER 17Z OR SO, LIGHT SNOW WILL DEVELOP FROM
WEST TO EAST, WHICH WILL START TO BRING RESTRICTIONS; STARTING
OUT AS MVFR, BUT BECOMING IFR-OR-WORSE BY THE MID-LATE
AFTERNOON. +SN (1/4SM VISBY) WILL BE POSSIBLE AT TIMES AS WELL. KELM
AND KAVP WILL SEE SOME SNOW INITIALLY, AND COULD SEE IFR VISBYS
FOR A FEW HOURS IN THE EARLY EVENING, THEN SOME SLEET IS LIKELY
TO MIX IN BY THE EVENING.
SLOW IMPROVEMENT IS EXPECTED FROM WEST TO EAST BY THE LATE
EVENING AS THE SNOW STARTS TO TAPER OFF, BUT LINGERING MVFR TO
IFR RESTRICTIONS ARE STILL EXPECTED.
OUTLOOK...
SATURDAY MORNING...A FEW LINGERING SNOW SHOWERS POSSIBLE WITH
OCCASIONAL RESTRICTIONS, OTHERWISE LINGERING MVFR TO FUEL
ALTERNATE CEILINGS.
SATURDAY AFTERNOON THROUGH SUNDAY MORNING...LINGERING MVFR
CEILING RESTRICTIONS POSSIBLE.
SUNDAY MIDDAY THROUGH SUNDAY NIGHT...RAIN AND RESTRICTIONS
LIKELY.
MONDAY THROUGH TUESDAY...COLD FRONTAL PASSAGE AND GUSTY WINDS
AS RAIN SHOWERS CHANGE BACK TO LAKE EFFECT SNOW SHOWERS,
ESPECIALLY NY TERMINALS AS LAKE EFFECT BECOMES DOMINANT.
RESTRICTIONS POSSIBLE, ESPECIALLY AT THE NY TERMINALS.
BGM WATCHES/WARNINGS/ADVISORIES
PA...WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
SATURDAY FOR PAZ039.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 7 AM EST SATURDAY
FOR PAZ038-043-044-047.
WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO NOON EST
SATURDAY FOR PAZ040-048-072.
NY...WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 7 AM EST
SATURDAY FOR NYZ009-015>018-023-025-036-037-044>046-055-
056.
WINTER WEATHER ADVISORY FROM NOON TODAY TO 7 AM EST SATURDAY
FOR NYZ022-024.
WINTER STORM WARNING FROM 1 PM THIS AFTERNOON TO NOON EST
SATURDAY FOR NYZ057-062.
DISCUSSION...AJG/MJM
AVIATION...BJG
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page