035
FXUS61 KOKX 192021
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
321 PM EST SUN JAN 19 2025
SYNOPSIS
DEEPENING LOW PRESSURE OFF THE MID ATLANTIC COAST WILL QUICKLY
PASS TO THE EAST OF THE AREA TONIGHT AND UP INTO THE CANADIAN
MARITIMES BY DAYBREAK MONDAY. HIGH PRESSURE BUILDS IN MONDAY
BRINGING AN ARCTIC AIRMASS TO THE AREA THAT REMAINS OVER THE
AREA THROUGH FRIDAY. A WEAK SYSTEM PASSES TUESDAY NIGHT INTO
WEDNESDAY, WITH AN OFFSHORE LOW POTENTIALLY IMPACTING PORTIONS
OF THE AREA IN THE THURSDAY NIGHT/FRIDAY PERIOD. A SLIGHT
WARMING TREND IS POSSIBLE NEXT WEEKEND.
NEAR TERM /THROUGH TONIGHT/
STEADIEST PRECIPITATION REMAINS NORTH AND WEST OF THE NYC METRO
IN ASSOCIATION WITH THE UPPER TROUGH. THIS WILL BEGIN TO EXPAND
EAST OVER THE NEXT COUPLE OF HOURS ACROSS NYC, LI, AND CT AS
LOW PRESSURE CONTINUES TO DEEPEN OFF THE MID ATLANTIC. THE
LATTER OF WHICH WILL PASS QUICKLY TO THE EAST THIS EVENING AND
UP INTO THE CANADIAN MARITIMES BY DAYBREAK MONDAY. MUCH OF THE
AREA WILL SEE ABOUT A 6-8HR WINDOW OF MAINLY SNOW, WITH 2 TO 4
HOURS OF IT POSSIBLY FALLING IN THE MODERATE TO OCCASIONALLY
HEAVY INTENSITY. 12Z HREF HAS 50 TO 80 PERCENT PROBABILITIES OF
INCH PER HOUR RATES THIS EVENING, BUT ONLY FOR AN HOUR OR TWO.
ALSO, PORTIONS OF EASTERN LI WILL INITIALLY MIX WITH RAIN AT THE
START. THE KEY TO SNOWFALL AMOUNTS WILL BE HOW QUICKLY TEMPERATURES
DROP AS A STRENGTHENING NORTHERLY FLOW DRAWS COLDER AIR DOWN
INTO THE REGION. THIS WILL ESPECIALLY BE CRITICAL ALONG THE
COAST WHERE TEMPERATURES TOPPED OUT AROUND 40 THIS AFTERNOON.
LIQUID EQUIVALENT AMOUNTS ON AVERAGE AREA EXPECTED TO RANGE FROM
0.4 TO 0.5" WITH SOME LOCALIZED ENHANCEMENTS. RATIOS WILL VARY
QUITE A BIT AT THE START WITH TEMPERATURES IN 30S, BUT AT SOME
POINT SHOULD GET INTO THE 15-10:1 RANGE AS TEMPERATURES FALL.
EXPECT SNOWFALL AMOUNTS OF 3 TO 5 INCHES ALONG THE COAST AND 5
TO 7 INCHES ACROSS THE INTERIOR. THIS IS SLIGHT ADJUSTMENT DOWN
(1/2-1"). THUS, NO CHANGES ARE PLANNED TO THE HAZARDS AT THIS
TIME. THE SNOW WILL BECOME LIGHT AND END AROUND MIDNIGHT FOR NYC
AND POINTS NORTH AND WEST AND 3 TO 4 AM FAR EASTERN AREAS.
TEMPERATURES WILL TUMBLE INTO THE UPPER TEENS TO AROUND 20 BY
DAYBREAK WITH N-NW WINDS GUSTING 20 TO 25 MPH, POSSIBLY UP TO
30 MPH. WIND CHILL VALUES FALL INTO THE SINGLE DIGITS OVERNIGHT
AND POSSIBLY AS LOW AS ZERO FOR THE INTERIOR. THESE VALUES FALL
SHORT OF COLD WEATHER ADVISORY (-5F AT THE COAST AND -10F
INLAND).
SHORT TERM /MONDAY THROUGH MONDAY NIGHT/
THE LOW DEPARTS TO THE NORTHEAST BY MONDAY MORNING WITH A STRONG
HIGH PRESSURE BUILDING IN FROM THE WEST. A TIGHT PRESSURE
GRADIENT WILL BRING A PERSISTENT NW FLOW WITH 20-25 MPH GUSTS
THROUGH THE DAY. THIS MAY RESULT IN BLOWING SNOW POSSIBLY
LOCALLY REDUCING VISIBILITIES AT TIMES.
THE PERSISTENT NW FLOW AND BUILDING HIGH PRESSURE WILL ADVECT A
FRIGID AIRMASS INTO THE AREA. HIGHS ON MONDAY WILL BE IN THE
20S WITH WIND CHILLS MAKING IT FEEL LIKE THE TEENS AND SINGLE
DIGITS. PERSISTENT WIND MONDAY NIGHT SHOULD LIMIT RADIATIONAL
COOLING BUT THE BUILDING FRIGID AIRMASS WILL ALLOW TEMPERATURES
TO FALL INTO THE SINGLE DIGITS FOR MOST OF THE AREA. WIND CHILLS
WILL HOWEVER MAKE IT FEEL LIKE ANYWHERE FROM NEAR 0 FOR EASTERN
LONG ISLAND TO -15 FOR PORTIONS OF THE INTERIOR LOWER HUDSON
VALLEY. MUCH OF THE AREA WILL SEE A WIND CHILL VALUE FROM 0 TO
-10.
LONG TERM /TUESDAY THROUGH SATURDAY/
NO SIGNIFICANT CHANGES TO THE OVERALL FCST THINKING IN THE
EXTENDED. WENT CLOSE TO THE NBM FOR TEMPS THRU THE PERIOD, WITH
TEMPS REMAINING BLW FREEZING THRU FRI, EXCEPT AT THE COASTS
WHERE HIGHS ON FRI COULD HIT THE MID 30S. POTENTIAL FOR A PERIOD
OF ZONAL FLOW OVER THE WEEKEND WHICH IS PROGGED TO PRODUCE
SLIGHTLY MILDER TEMPS. THE PLACEMENT OF THE POLAR FRONT WILL BE
DIFFICULT TO PINPOINT THIS FAR OUT, SO TEMPS COULD SWING MUCH
COLDER OR WARMER DEPENDING ON WHERE THE BOUNDARY SETS UP. IT
LOOKS LIKE THE NBM IS LEANING TOWARDS THE COLDER SIDE ATTM.
BOTH THE GFS AND ECMWF HAVE BACKED OFF ON THE LGT SNOW CHCS FOR TUE
NGT INTO WED, DESPITE THE PASSAGE OF THE UPR TROF. THE NBM POPS
HOWEVER WERE STILL IN CHC CATEGORY FOR MOST OF THE AREA, SUGGESTING
THAT THE CONSENSUS HAS NOT LATCHED ONTO THIS TREND YET. WILL STICK
WITH THE HIGHER POPS FOR NOW AND SEE IF THE TREND HOLDS.
STILL CHCS FOR SNOW NOW LATE THU INTO FRI, ESPECIALLY ERN AND SRN
AREAS WITH AN OFFSHORE LOW. THERE IS NOT SOLID AGREEMENT AMONGST THE
MODELS SO CONFIDENCE IS LOW. NBM POPS IN THE 20-30 RANGE ATTM.
POTENTIAL FOR A FRONTAL BOUNDARY TO STALL OVER THE CWA DURING THE
WEEKEND. THIS COULD PRODUCE PERIODS OF MAINLY LGT PCPN, BUT
PINPOINTING THE BOUNDARY THIS FAR OUT IS VERY LOW CONFIDENCE.
AVIATION /20Z SUNDAY THROUGH FRIDAY/
LOW PRESSURE DEVELOPS ALONG THE MID ATLANTIC COAST, PASSING
SOUTHEAST OF THE AREA TONIGHT.
MVFR/VFR TO START THEN CONDITIONS LOWER TO IFR/LIFR IN SNOW
LATE THIS AFTERNOON AND EVENING. THE SNOW TAPERS OFF 03-06Z,
WITH VFR THEREAFTER.
WINDS VEER TO THE N THEN NE TODAY WITH SPEEDS GENERALLY 10-12KT.
WINDS BECOME NW AFTER 22-00Z. GUSTS ARE EXPECTED TONIGHT AND
MONDAY WITH GUSTS IN THE LOWER AND MIDDLE 20KT RANGE.
EXPECTED SNOWFALL ACCUMULATIONS:
NYC TERMINALS, BDR, ISP: 4-6" HPN: 4-8" SWF: 5-8"
...NY METRO (KEWR/KLGA/KJFK/KTEB) TAF UNCERTAINTY...
AMENDMENTS POSSIBLE FOR THE TIMING ON SNOW THIS
AFTERNOON/EVENING. OCCASIONAL GUSTS POSSIBLE LATE THIS
AFTERNOON/EVENING AND AFTER MIDNIGHT.
OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY
MONDAY AFTERNOON: VFR. NW WIND GUSTS 20-25 KT.
TUESDAY: VFR. W WIND GUSTS AROUND 20 KT.
WEDNESDAY: CHANCE OF MVFR OR LOWER IN -SN, PARTICULARLY COASTAL
TERMINALS.
THURSDAY: VFR.
FRIDAY: MAINLY VFR, CHANCE OF MVFR IN LIGHT SNOW.
DETAILED INFORMATION, INCLUDING HOURLY TAF WIND COMPONENT FORECASTS,
CAN BE FOUND AT: HTTPS:/WWW.WEATHER.GOV/ZNY/N90
MARINE
WAVE HEIGHTS NEAR 5 FEET ARE PROVIDING FOR A CONTINUED SCA ON
THE CENTRAL AND EASTERN OCEAN ZONES THROUGH TODAY. WINDS AND
SEAS THEN INCREASE TONIGHT ACROSS ALL FORECAST WATERS AS THE LOW
PRESSURE PASSES NEARBY. AS THE LOW PULLS AWAY TONIGHT, SCA
CONDITIONS SHOULD PREVAIL ACROSS ALL WATERS WITH A GUSTY WNW
BEHIND ANOTHER COLD FRONT. THERE WILL BE A LOW END CHANCE FOR
SOME GALE GUSTS ON THE OCEAN.
MONDAY, WIDESPREAD SCA CONDITIONS EXPECTED FOR ALL WATERS DUE TO
WIND GUSTS, FOR OCEAN BOTH WIND GUSTS AND SEAS. DECREASING TREND TO
WINDS AND SEAS MONDAY NIGHT, BUT OCEAN WILL PROBABLY STILL HAVE SCA
CONDITIONS THROUGH TUESDAY MORNING. NON-OCEAN WATERS STAY BELOW
SCA FOR MONDAY NIGHT. THE OCEAN COULD HAVE SOME LINGERING SCA
CONDITIONS TUESDAY MORNING WITH OTHERWISE BELOW SCA CONDITIONS
FOR THE WATERS. FOR TUESDAY AFTERNOON THROUGH THURSDAY, SUB-SCA
CONDITIONS FORECAST FOR ALL WATERS.
ALSO, WOULD EXPECT SOME LIGHT FREEZING SPRAY FOR TONIGHT
THROUGH EARLY NEXT WEEK FOR PARTS OF THE WATERS.
HYDROLOGY
NO HYDROLOGIC ISSUES ARE ANTICIPATED THROUGH SATURDAY.
OKX WATCHES/WARNINGS/ADVISORIES
CT...WINTER STORM WARNING UNTIL 4 AM EST MONDAY FOR CTZ005>008.
WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR CTZ009>012.
NY...WINTER STORM WARNING UNTIL 4 AM EST MONDAY FOR NYZ067>070.
WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR NYZ071>075-
078>081-176>179.
NJ...WINTER STORM WARNING UNTIL 4 AM EST MONDAY FOR NJZ002-004-
103>105-107.
WINTER WEATHER ADVISORY UNTIL 4 AM EST MONDAY FOR NJZ006-106-
108.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST MONDAY
FOR ANZ331-332-335-338-340-345.
SMALL CRAFT ADVISORY UNTIL 7 AM EST TUESDAY FOR ANZ350-353.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 7 AM EST
TUESDAY FOR ANZ355.
SYNOPSIS...DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...JMC
AVIATION...BC
MARINE...JMC/MW
HYDROLOGY...JMC/MW
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