767
FXUS61 KBGM 211753
AFDBGM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BINGHAMTON NY
1253 PM EST SAT DEC 21 2024
SYNOPSIS
LAKE EFFECT SNOW SHOWERS ARE EXPECTED TO CONTINUE THROUGH
TONIGHT, ESPECIALLY ACROSS THE FINGER LAKES REGION. VERY COLD
WEATHER IS EXPECTED THROUGH SUNDAY NIGHT. ANOTHER CLIPPER
SYSTEM WILL ARRIVE MONDAY NIGHT INTO TUESDAY WITH ANOTHER CHANCE
FOR LIGHT WINTRY PRECIPITATION AS TEMPERATURES MODERATE AGAIN
HEADING TOWARDS CHRISTMAS.
NEAR TERM /THROUGH SUNDAY/
1025 AM UPDATE:
BANDS OF LAKE EFFECT SNOW HAVE BEEN A BIT MORE ROBUST THIS
MORNING THAN PREVIOUSLY EXPECTED, MAINLY DUE TO ENHANCEMENT FROM
THE FINGER LAKES. WITH THIS UPDATE, MADE SIGNIFICANT ADJUSTMENTS
TO POPS AND ALSO INCREASED ADDITIONAL SNOWFALL AMOUNTS FOR AREAS
DOWNWIND OF THE FINGER LAKES. BECAUSE OF HOW NARROW THE FINGER
LAKES ARE, THE BANDS OF HEAVIER LAKE EFFECT SNOW HAVE BEEN VERY
NARROW AND THEREFORE SNOWFALL AMOUNTS WILL VARY SIGNIFICANTLY
WITHIN JUST A FEW MILES.
HEADLINE-WISE, WE ALSO EXPANDED THE WINTER WEATHER ADVISORY FOR
THE LAKE EFFECT SNOW TO INCLUDE TIOGA COUNTY, NY SINCE THERE HAS
BEEN A PERSISTENT BAND OF LAKE EFFECT SNOW THERE. ADDITIONAL
SNOWFALL AMOUNTS OF 2 TO 5 INCHES ARE EXPECTED IN THE ADVISORY
AREAS. WHEN COMBINING THE SNOWFALL FROM THE SYNOPTIC SYSTEM FROM
YESTERDAY/LAST NIGHT WITH TODAY/TONIGHT'S LAKE EFFECT SNOW,
THERE WILL BE SOME SNOW TOTALS THAT WILL EXCEED WARNING
CRITERIA (GREATER THAN 7 INCHES), BUT THESE ARE BEING TREATED
AS SEPARATE EVENTS DUE TO THE LULL THAT OCCURRED BETWEEN THESE
TWO "EVENTS" AND THE FACT THAT THE EVENTS COMBINED ARE BASICALLY
OVER A 36 HOUR PERIOD.
640 AM UPDATE...
EXPANDED THE CHANCES OF PRECIPITATION ACROSS THE FINGER LAKES AS
THE LAKE EFFECT THIS MORNING HAS BEEN MORE WIDESPREAD. A COUPLE
OF HEALTHY FINGER LAKE ENHANCED SNOW BANDS ARE EXTENDING INTO
TIOGA AND SUSQUEHANNA COUNTIES THAT COULD PRODUCE A COUPLE
INCHES OF LOW DENSITY SNOW OVER THE NEXT SEVERAL HOURS.
345 AM UPDATE...
THE SYNOPTIC SNOW HAS MOVED OUT OF THE REGION AS THE INVERTED
TROUGH FLATTENS OUT. STRONG COLD AIR ADVECTION WILL BRING IN 850
MB TEMPS OF DOWN AROUND -20C THIS AFTERNOON AND EVENING. LAKE
EFFECT SNOW IS ALREADY DEVELOPING AND WILL PERSIST THROUGH THE
DAY THROUGH AROUND MIDNIGHT TONIGHT. WHILE WIND SHEAR AND DEPTH
OF BOUNDARY LAYER IS NOT SUPER FAVORABLE FOR WELL ORGANIZED SNOW
BANDS, THERE WILL BE A LARGE DIFFERENCE IN WATER TEMP VS AIR
TEMP SO SOME BANDS WILL FORM. LIFT WILL BE RIGHT THROUGH THE
DENDRITIC GROWTH ZONE WITH HIGH SNOW RATIOS OF 20:1 OR GREATER.
SURFACE WIND DIRECTIONS WILL BE AROUND 320 DEGREES WHICH IS ALSO
FAVORABLE FOR FINGER LAKE EFFECT SNOW SO CHANCES OF
PRECIPITATION AS WELL AS QPF WERE RAISED JUST DOWNWIND OF SENECA
AND CAYUGA LAKES TO BUMP UP SNOW TOTALS ABOUT AN INCH. WITH THE
POORLY ORGANIZED SNOW BANDS, THERE SHOULD NOT BE ANY LONG
RESIDENCE TIMES OF THE BANDS IN ONE LOCATION BUT AS THEY MOVE
ABOUT, A WIDESPREAD AREA ON WESTERN CNY AND THE EASTERN FINGER
LAKES COULD GET UP NEAR 6 INCHES IN SPOTS BY TOMORROW MORNING
SO A WINTER WEATHER ADVISORY HAS BEEN ISSUED. WIND GUSTS OF 15
TO 20 MPH THIS AFTERNOON COUPLED WITH THE LOW DENSITY SNOW WILL
CAUSE AREAS OF BLOWING SNOW ESPECIALLY NEAR OPEN FIELDS.
TONIGHT WITH THE COLD AIR IN PLACE AS WELL AS SOME WIND
CONTINUING, LOW TEMPERATURES FALL INTO THE SINGE DIGITS BOTH
ABOVE AND BELOW 0 WITH WIND CHILLS MOSTLY BELOW 0. RIGHT NOW THE
HIGHER ELEVATIONS OF THE CATSKILLS AS WELL AS PORTIONS OF THE
TUG HILL MAY SEE WIND CHILLS FALL TO NEAR -15F. THE HIGHEST
CONFIDENCE IN THOSE COLDER WIND CHILLS IS IN DELAWARE COUNTY AS
WINDS WILL REMAIN ELEVATED IN THE HIGHER TERRAIN.
LAKE EFFECT SNOW WILL WIND DOWN BY SUNDAY MORNING AS HIGH
PRESSURE BUILDS IN AND LOW LEVEL FLOW WEAKENS. SOME WARMER
TEMPERATURES BEGIN TO ADVECT IN ALOFT BUT THE COLD AIR IN PLACE
AND LOWEST SUN ANGLE OF THE YEAR MEANS NOT MUCH WARMING UP WILL
OCCUR.
SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/
330 AM UPDATE:
ANOTHER VERY COLD NIGHT IS EXPECTED JUST AHEAD OF NEXT WEEK. WHILE
850MB TEMPERATURES WILL ACTUALLY RISE SUNDAY NIGHT WITH THE
COLD AIRMASS RETREATING, CLEAR SKIES, LIGHT WINDS, AND A FRESH
SNOWPACK WILL SET THE STAGE FOR EFFICIENT RADIATIONAL COOLING.
THEREFORE CONTINUED TO GO SEVERAL DEGREES BELOW THE NBM GUIDANCE
FOR FORECAST LOWS. CURRENTLY FORECASTING LOWS TO BE IN THE
LOWER SINGLE DIGITS WITH MANY AREAS AT OR A FEW DEGREES BELOW
ZERO. RIGHT NOW FORECAST LOW TEMPERATURES AND WIND CHILLS ARE
EXPECTED TO FALL SHORT OF THE NEW COLD WEATHER ADVISORY CRITERIA
(EITHER TEMPERATURE OR WIND CHILL OF -15F OR LOWER), BUT THIS
WILL CONTINUE TO BE MONITORED WITH UPCOMING UPDATES.
HIGH PRESSURE WILL REMAIN IN PLACE ON MONDAY AND THE AIRMASS
WILL BE ON A MODERATING TREND. AS A RESULT, MOSTLY SUNNY SKIES
ARE EXPECTED WITH HIGHS IN THE 20S. HIGHER CLOUDS WILL INCREASE
LATE IN THE DAY AHEAD OF THE NEXT SYSTEM.
ANOTHER CLIPPER SYSTEM WILL BRING WIDESPREAD LIGHT SNOW TO THE
REGION MONDAY NIGHT INTO TUESDAY MORNING. THIS NEXT ROUND OF
SNOW WILL BRING A 1 TO 3 INCHES ACROSS MOST OF THE AREA WITH
LOCALIZED AMOUNTS UP TO 4 INCHES POSSIBLE.
LONG TERM /TUESDAY THROUGH SATURDAY/
335 AM UPDATE:
CLIPPER SYSTEM WILL CONTINUE TO DROP LIGHT SNOW ACROSS THE AREA
ON TUESDAY. A WHITE CHRISTMAS IS ALMOST CERTAIN AT THIS POINT.
THIS SNOW WILL BE IN ADDITION TO WHAT IS ALREADY ON THE GROUND
AND TEMPERATURES WILL ONLY TOP OUT IN THE LOW TO MID 30S ON
TUESDAY, SO NOT MUCH MELTING IS EXPECTED BEFORE CHRISTMAS DAY.
BY WEDNESDAY/CHRISTMAS DAY, HIGH PRESSURE LOOKS TO MOVE BACK
INTO THE AREA, WHICH WILL LIKELY RESULT IN A PRECIPITATION-FREE
DAY AND SEASONABLE TEMPERATURES. THIS MAY MARK THE START OF A
RARE MULTI-DAY STRETCH OF MAINLY PRECIPITATION-FREE WEATHER FOR
THIS TIME OF THE YEAR, AS A RIDGE BUILDS IN. TEMPERATURES WILL
ALSO INCREASE THROUGH THE REMAINDER OF THE WEEK AS THE RIDGE IS
EXPECTED TO HOLD RIGHT INTO THE WEEKEND.
AVIATION /18Z SATURDAY THROUGH THURSDAY/
LAKE EFFECT SNOW SHOWERS ARE IMPACTING ALL OF THE CENTRAL NY
TERMINALS EXCEPT FOR KRME THIS AFTERNOON. THIS WILL RESULT IN
MAINLY MVFR RESTRICTIONS, BUT IFR RESTRICTIONS ARE EXPECTED IN
ANY STEADIER SNOW SHOWERS (ESPECIALLY AT KITH, KBGM, AND KSYR).
SOME SNOW SHOWERS MAY EVEN REACH KAVP THIS AFTERNOON SO A TEMPO
FOR MVFR RESTRICTIONS SNOW SHOWERS WAS INCLUDED THERE. SNOW WILL
TAPER OFF OVERNIGHT TONIGHT WITH KITH LIKELY SEEING THE SNOW
LINGER THE LONGEST. SOME LINGERING MVFR CEILINGS ARE EXPECTED TO
PERSIST AT MOST OF THE CENTRAL NY TERMINALS SUNDAY MORNING, BUT
GRADUAL IMPROVEMENT IS EXPECTED BY SUNDAY AFTERNOON.
OUTLOOK...
SUNDAY AFTERNOON...BECOMING MAINLY VFR.
MONDAY...MAINLY VFR.
MONDAY NIGHT THROUGH TUESDAY...OCCASIONAL RESTRICTIONS POSSIBLE
IN SCATTERED SNOW SHOWERS.
WEDNESDAY THROUGH THURSDAY...MAINLY VFR.
BGM WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NY...WINTER WEATHER ADVISORY UNTIL 4 AM EST SUNDAY FOR NYZ016>018-
025-044-055.
COLD WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EST SUNDAY
FOR NYZ057.
SYNOPSIS...BJG
NEAR TERM...AJG/BJG
SHORT TERM...BJG/MPK
LONG TERM...BJG/MPK
AVIATION...BJG
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