939
FXUS61 KOKX 181932
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
332 PM EDT THU SEP 18 2025
SYNOPSIS
WEAK LOW PRESSURE CONTINUES TO MOVE FARTHER AWAY TO THE
NORTHEAST THROUGH TONIGHT. MEANWHILE A COLD FRONT APPROACHES
FROM THE NORTH AND WEST. THIS COLD FRONT MOVES ACROSS EARLY
FRIDAY. HIGH PRESSURE MOVES IN FROM SOUTHEAST CANADA THEREAFTER
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. A WEAK FRONT WILL
MOVE THROUGH TUESDAY NIGHT, THEN RETURN NORTH AS A SLOW MOVING
WARM FRONT WEDNESDAY INTO THURSDAY.
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/
NUMERICAL WEATHER PREDICTION MODELS SHOW THAT MID LEVELS EXHIBIT
NOT MUCH HEIGHT CHANGE, RIDGE TO THE WEST AND TROUGH TO THE
NORTH. SURFACE, A COLD FRONT APPROACHES FROM THE NORTH AND WEST.
THIS WILL MOVE THROUGH THE AREA EARLY ON FRIDAY.
WINDS WILL BE LIGHT, SW TO NW DIRECTION TONIGHT, BECOMING ALL NW
OVERNIGHT INTO FRIDAY MORNING AS THE COLD FRONT MOVES ACROSS.
CLOUDS WILL BE MINIMAL WITH THE FRONT WITH WINDS STAYING UP
SLIGHTLY TO LIMIT RADIATIONAL COOLING.
NBM APPEARED TO BE TOO WARM AND LEANED MORE TOWARDS RELATIVELY
COOLER MOS FOR THE FORECAST MIN TEMPERATURES FOR LOCATIONS
THAT ARE MORE RURAL AND COOL OFF MORE RAPIDLY. USED THE MAV/MET
MOS BLEND INSTEAD. LOWS RANGE FROM THE LOWER 50S TO UPPER 60S.
A FEW LOCATIONS WITHIN THE OUTLYING AND RURAL SECTIONS COULD
DEVELOP SOME FOG LATE TONIGHT INTO EARLY FRIDAY MORNING WITH
RADIATIONAL COOLING AND VERY LIGHT WINDS. LEFT AS SOME PATCHY
FOG IN FORECAST GRIDS.
SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/
THE COLD FRONT TO START THE SHORT TERM IS EXPECTED TO BE
SOUTHEAST OF THE REGION WITH ALL NW FLOW FOR EARLY FRIDAY.
NW FLOW EXPECTED TO REMAIN THROUGH THE DAY, AS SURFACE HIGH
PRESSURE BUILDS IN FROM THE NORTH AND WEST. THE CENTER OF HIGH
PRESSURE WILL BE IN ONTARIO FRIDAY AND HEADING INTO QUEBEC
SATURDAY.
WITH NW PRIMARY MODE OF WIND DIRECTION DURING THE DAY,
DOWNSLOPE WILL BE EFFECTIVE AT ALLOWING COASTAL LOCATIONS TO BE
JUST AS WARM IF NOT SLIGHTLY WARMER THAN INTERIOR LOCATIONS.
NBM WAS ADJUSTED A DEGREE WARMER ALONG CT AND NYC/LI SOUTHERN
COASTLINES. UPPER 70S TO MID 80S RANGE OF HIGH TEMPERATURES
FORECAST.
FOR FRIDAY NIGHT, MODELS CONVEY A STRENGTHENING OF THE HIGH
PRESSURE MOVING IN. THE HIGH PRESSURE CONTINUES TO BUILD INTO
THE LOCAL AREA BUT WITH AN INCREASE IN PRESSURE GRADIENT. THIS
WILL ALLOW FOR AN INCREASE IN NE FLOW, WHICH WILL MITIGATE
RADIATIONAL COOLING. USED A BLEND OF MAV AND MET MOS ALONG WITH
NBM WITH GREATER WEIGHT TOWARDS MAV AND MET, WITH EACH 40
PERCENT WEIGHT. FORECAST LOWS RANGE FROM MID 40S TO NEAR 60.
RIDGING IN THE MID LEVELS SATURDAY THROUGH SATURDAY NIGHT. THIS
WILL HELP PROMOTE SUBSIDENCE AND KEEP CLOUD COVERAGE MINIMAL.
FOR SATURDAY, THE NE FLOW CONTINUES WITH GUSTY WINDS FOR THE DAY
CLOSER TO THE COAST, NEAR 20 MPH. GUSTS SUBSIDE TOWARDS THE END
OF THE DAY AND AT NIGHT. THE FLOW BECOMES MORE EASTERLY. A MUCH
COOLER DAY IS EXPECTED WITH FORECAST MAX TEMPERATURES MOSTLY IN
THE LOWER 70S. LOWS SATURDAY NIGHT, WHILE PARTIALLY MITIGATED
WITH THE EASTERLY WINDS, ARE STILL EXPECTED TO DROP NEAR
SLIGHTLY COOLER VALUES THAN THOSE OF FRIDAY NIGHT, MID 40S TO
UPPER 50S. TEMPERATURES FOR SATURDAY AND SATURDAY NIGHT FOLLOWED
THE NBM.
WILL HAVE TO WATCH FOR POTENTIAL LOW STRATUS AND/OR FOG
DEVELOPMENT SATURDAY NIGHT WITH THE EASTERLY FLOW CONTINUING.
HAVE AREAS ACROSS THE NORTHERN PARTS OF THE REGION WITH PATCHY
FOG LATE SATURDAY NIGHT.
LONG TERM /SUNDAY THROUGH THURSDAY/
THE PERIOD STARTS OFF WITH AN ELONGATED SFC HIGH PRESSURE RIDGE
EXTENDING WESTWARD FROM THE NORTH ATLANTIC INTO NEW ENGLAND AND
THE MID ATLANTIC STATES, WITH WEAK RIDGING ALOFT, WHILE THE
TROUGHING THAT HAS PERSISTED OFF THE SE COAST FOR SOME TIME
FINALLY LIFTS OUT INTO THE ATLANTIC. WE SHOULD SEE FAIR WX
DURING THIS TIME, WITH A GENERAL E FLOW ON SUNDAY, BECOMING SE-S
ON MON. TEMPS ON SUNDAY WILL BE A LITTLE ON THE COOL SIDE, WITH
HIGHS IN THE UPPER 60S/LOWER 70S, THEN MODERATING CLOSE TO
NORMAL FOR MON WITH HIGHS IN THE 70S THROUGHOUT.
ON TUE, A NRN STREAM TROUGH WILL SEND A WEAK FRONT TOWARD THE
AREA, THAT SHOULD MOVE THROUGH TUE NIGHT. THE FRONT WILL BE
FAIRLY MOISTURE STARVED, SO HAVE FORECAST ONLY SLIGHT CHANCE POP
FOR SOME SHOWERS LATE DAY TUE INTO TUE NIGHT. TEMPS WILL BE
ABOVE NORMAL ON A SW FLOW, WITH HIGHS IN THE LOWER 80S FOR THE
NYC METRO AREA AND MOST OF THE INTERIOR.
MODEL GUIDANCE DIVERGES SOMEWHAT LATER IN THE WEEK BUT EITHER
WAY SUGGESTS A BLOCKIER PATTERN UNFOLDING, WITH THE ECMWF
FORECASTING A REX BLOCK OVER THE CENTRAL STATES AS RIDGING
BUILDS INTO CENTRAL CANADA AND A CLOSED LOW FORMS OVER THE
SOUTHER PLAINS, WHILE THE GFS HAS MORE OF AN OMEGA BLOCK FROM
THE NORTHERN PLAINS AND CENTRAL CANADA OVER TO NEW ENGLAND.
EITHER WAY THIS SETUP SUGGESTS SFC HIGH PRESSURE OVER
CENTRAL/ERN CANADA, WITH SOME ENERGY UNDERCUTTING THE GENERAL
BLOCKINESS TO SEND A SFC WARM FRONT SLOWLY TOWARD THE AREA WED
INTO THU. HAVE FORECAST CHANCE POP FOR WED NIGHT FOR NYC
NORTH/WEST AND LONG ISLAND, AND SLIGHT CHANCE OTHERWISE FOR WED
NIGHT INTO THU. TEMPS DURING THIS TIME FRAME SHOULD REMAIN ABOVE
NORMAL.
AVIATION /19Z THURSDAY THROUGH TUESDAY/
A COLD FRONT APPROACHES TONIGHT AND MOVES ACROSS THE TERMINALS
ON FRIDAY.
VFR CONDITIONS PREVAILS THROUGH FRIDAY.
NW-W WITH MID TO LATE AFTERNOON SW SEA BREEZES LIKELY AT COASTAL
TERMINALS. WINDS WILL VEER TO THE SW AFTER 00Z AND AS SPEEDS
DIMINISH TO AROUND 5 KT, THEN SHIFT AROUND TO THE NW AROUND 10
KT OVERNIGHT AND INTO FRIDAY.
...NY METRO (KEWR/KLGA/KJFK/KTEB) TAF UNCERTAINTY...
TIMING OF SEA BREEZES THIS AFTERNOON COULD BE OFF BY 1-2 HOURS.
OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY
FRIDAY THROUGH TUESDAY: VFR.
MARINE
CONDITIONS ARE FORECAST TO REMAIN BELOW SCA THRESHOLDS THROUGH
SATURDAY NIGHT. THE CONDITIONS GET RELATIVELY CLOSE TO SCA
THRESHOLDS LATE FRIDAY NIGHT INTO EARLY SATURDAY WITH WIND GUSTS
UP TO 20 KT AND OCEAN SEAS BUILDING TO NEAR 4 FT.
PERSISTENT E FLOW ON SHOULD KEEP OCEAN SEAS AT 3-4 FT ON SUNDAY.
THEREAFTER THE WAVE HEIGHT FORECAST IS UNCERTAIN, AND WILL
DEPEND ON THE FUTURE TRACK AND INTENSITY OF TS GABRIELLE WELL
OUT IN THE ATLANTIC. ATTM NWPS SUGGESTS POTENTIAL FOR SETS OF
5-FT SE SWELLS FROM MON AFTERNOON INTO TUE.
HYDROLOGY
THERE ARE NO HYDROLOGIC CONCERNS ATTM.
TIDES/COASTAL FLOODING
WITH A 2-FT/8 SEC SWELL AND MOSTLY OFFSHORE FLOW 10 KT OR LESS,
PERHAPS SOME LATE AFTERNOON SW SEA BREEZES AT THE SAME SPEEDS,
HAVE FORECAST A LOW RIP CURRENT RISK FOR FRI. AS ENE FLOW AFTER
A COLD FRONTAL PASSAGE INCREASES TO AROUND 15 KT SAT MORNING AND
SEAS BUILD TO 4 FT/5 SEC (MORE FAVORABLE FOR LONGSHORE
CURRENTS), THE RIP CURRENT RISK SHOULD BECOME MODERATE ON SAT.
OKX WATCHES/WARNINGS/ADVISORIES
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
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