995  
FXUS61 KOKX 122355  
AFDOKX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NEW YORK NY  
755 PM EDT MON MAY 12 2025  
   
SYNOPSIS  
 
A WEAK BACKDOOR COLD FRONT MOVES ACROSS THE REGION TONIGHT AS  
HIGH PRESSURE BUILDS SOUTHWARD OFF THE NEW ENGLAND COAST.  
MEANWHILE, AN AREA OF LOW PRESSURE SLOWLY APPROACHES FROM THE  
MID-ATLANTIC TUESDAY AND WEDNESDAY AND PASSES NEARBY DURING  
THURSDAY. A WARM FRONT THEN MOVES THROUGH DURING FRIDAY,  
FOLLOWED BY A COLD FRONT ON SATURDAY INTO SATURDAY NIGHT. WEAK  
HIGH PRESSURE WILL THEN BE IN PLACE FOR SUNDAY AND MONDAY WITH A  
FEW WEAK COLD FRONTS OR TROUGHS POSSIBLY PASSING THROUGH.  
 
 
   
NEAR TERM /UNTIL 6 AM TUESDAY MORNING/  
 
THE FORECAST REMAINS MAINLY ON TRACK. MINOR ADJUSTMENTS WERE  
MADE TO SOME OF THE HOURLY FORECAST ELEMENTS WITH THIS UPDATE.  
 
CLOUDS GRADUALLY INCREASE AS A BROAD AREA OF LOW PRESSURE APPROACHES  
FROM THE SOUTH. MEANWHILE, HIGH PRESSURE WELL NORTH OF THE REGION  
GRADUALLY BUILDS SOUTHEASTWARD, FORCING A BACK DOOR COLD FRONT TO  
APPROACH FROM THE NORTHEAST. WITH THE LOW PRESSURE SYSTEM  
APPROACHING FROM THE SOUTH, SOME RAIN SHOWERS MAY DEVELOP AFTER  
MIDNIGHT, MAINLY ACROSS NE NJ AND NYC. WILL INTRODUCE SOME  
CHANCE OR SLIGHT CHANCE POPS. ANY SHOWERS SHOULD REMAIN LIGHT IN  
INTENSITY. THE EASTWARD PROGRESSION OF THIS BAND OF SCATTERED  
SHOWERS REMAINS A BIT UNCERTAIN AS THE SHOWERS WILL BE RUNNING  
INTO THE DRIER AIRMASS FROM THE HIGH PRESSURE OFFSHORE.  
 
WITH INCREASING CLOUD COVER, TEMPERATURES SHOULD REMAIN SOMEWHAT  
MILD, WITH LOWS ONLY FALLING INTO THE 50S TO LOWER 60S IN THE NYC  
METRO AREA.  
 
 
   
SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/  
 
A BACKDOOR COLD FRONT CONTINUES TO MOVE INTO THE AREA TUESDAY  
MORNING AND EITHER MOVES THROUGH THE ENTIRE AREA OR STALLS OVER THE  
AREA AS A STATIONARY BOUNDARY. MEANWHILE, THE BROAD AREA OF LOW  
PRESSURE CONTINUES TO SPREAD PRECIPITATION INTO PORTIONS OF THE CWA.  
THE BEST CHANCES WILL BE ACROSS THE WESTERN HALF OF THE CWA,.  
 
THERE REMAINS SOME UNCERTAINTY WITH JUST HOW FAR EAST THE  
PRECIPITATION REACHES. SOME EASTERN AREAS MAY REMAIN MOSTLY DRY  
DURING THIS TIMEFRAME. CLOUDY SKIES SHOULD PREVENT TEMPERATURES FROM  
RISING TOO MUCH TUESDAY WITH HIGHS IN THE UPPER 60S TO MIDDLE 70S  
FOR THE NORTHEASTERNMOST AREAS. TUESDAY NIGHT LOWS ONLY FALL INTO  
THE MIDDLE AND UPPER 50S.  
 
 
   
LONG TERM /WEDNESDAY THROUGH MONDAY/  
 
MODELS IN GOOD AGREEMENT WITH A CLOSED H5 LOW OPENING UP AS IT HEADS  
NE INTO THE GREAT LAKES REGION WEDNESDAY INTO WEDNESDAY NIGHT.  
ASSOCIATED TROUGH AXIS SHIFTS THROUGH THE FORECAST AREA DURING  
THURSDAY NIGHT. AT THE SURFACE, WEAKENING LOW PRESSURE OVER THE MID-  
ATLANTIC ON WEDNESDAY SLOWLY APPROACHES AND PASSES OVER OR NEARBY US  
AT SOME POINT IN THE THURSDAY TO THURSDAY NIGHT PERIOD. RAIN WILL BE  
POSSIBLE AT ANY GIVEN TIME DURING THIS PERIOD, HOWEVER IT APPEARS  
THAT IT WILL BE MOST LIKELY DURING THE DAYTIME WEDNESDAY. THIS IS  
WHEN THE STRONGEST H8 THETA-E ADVECTION AND ISENTROPIC LIFT WITH THE  
HELP OF LLJ UPWARD FORCING INTERACT WITH THE DEEPEST MOISTURE. THE  
MAGNITUDE OF THE MOISTURE DOESN'T APPEAR TO BE SIGNIFICANTLY  
ANOMALOUS, SO HYDROLOGIC IMPACTS ARE NOT ANTICIPATED AT THIS TIME.  
EVEN THE NBM PROBABILITIES OF 6-HOUR RAINFALL BEING GREATER THAN A  
HALF INCH THROUGH THE PERIOD ARE VERY LOW.  
 
EVEN WITH THE STRONGEST FORCING AND DEEPEST MOISTURE SHIFTING AWAY,  
RAINFALL IS STILL LIKELY DURING WEDNESDAY NIGHT AS THE  
AFOREMENTIONED WEAK LOW APPROACHES. INDICATIONS ARE THAT THE LOW  
WEAKENS INTO A TROUGH BY THE TIME OF ITS CLOSEST APPROACH, SO POPS  
ARE CAPPED AT CHANCE (40-50% MOST LOCATIONS) FOR THURSDAY, BUT WENT  
ABOVE NBM GUIDANCE CONSIDERING THE PROXIMITY OF THE TROUGH AS WELL  
AS A SHORTWAVE AND TROUGH AXIS ALOFT SHIFTING THROUGH.  
 
A WARM FRONT THEN SHIFTS THROUGH DURING FRIDAY WITH WITH RIDGING  
ALOFT MITIGATING SHOWER CHANCES. A COLD FRONT FOLLOWS FOR SATURDAY  
INTO SATURDAY NIGHT WITH ADDITIONAL SHOWERS AND MAYBE A THUNDERSTORM.  
 
UNCERTAINTY THEN INCREASES FOR SUNDAY AND MONDAY, STEMMING FROM  
GLOBAL MODEL DISAGREEMENT ON THE PLACEMENT OF AN UPPER LOW. THERE'S  
GENERAL AGREEMENT THAT IT REMAINS TO OUR NORTH, BUT STILL CANNOT  
RULE OUT A DIURNALLY-DRIVEN SHOWER BOTH DAYS AS A SURFACE TROUGH AND  
CYCLONIC FLOW ALOFT ARE POTENTIALLY IN THE AREA.  
 
 
   
AVIATION /00Z TUESDAY THROUGH SATURDAY/  
 
DURING THE TAF PERIOD, A WEAK COLD FRONT MOVES INTO THE AREA  
FROM THE NORTH. HIGH PRESSURE WILL CONTINUE MOVING OFFSHORE.  
LARGE AREA OF LOW PRESSURE APPROACHES SLOWLY FROM THE SOUTHWEST.  
 
VFR CONDITIONS EXPECTED THROUGH EARLY TUESDAY AFTERNOON. MVFR  
CHANCES INCREASE FROM WEST TO EAST THEREAFTER FOR THE REST OF  
THE TAF PERIOD.  
 
SOME LIGHT RAIN IS POSSIBLE EARLY TUESDAY FOR NYC AND LOWER  
HUDSON VALLEY TERMINALS. THERE ARE HIGHER CHANCES OF RAIN MOVING  
INTO NYC AND LOWER HUDSON VALLEY TERMINALS TUESDAY AFTERNOON  
INTO START OF TUESDAY EVENING WITH MVFR CHANCES ALSO INCREASING.  
TO THE EAST, EXPECTING MAINLY DRY CONDITIONS AND VFR CONDITIONS  
EXPECTED TO PREVAIL THROUGH MUCH OF THE AFTERNOON.  
 
WINDS THROUGH THE TAF PERIOD AROUND 10 KTS OR LESS. WIND  
DIRECTION SOUTHERLY THIS EVENING, WITH SOME VARIABILITY  
OVERNIGHT, BECOMES GENERALLY MORE EASTERLY TUESDAY.  
 
...NY METRO (KEWR/KLGA/KJFK/KTEB) TAF UNCERTAINTY...  
 
MVFR AND IFR TIMING COULD BE A FEW HOURS OFF FROM TAF.  
   
OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY  
 
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT: LOW STRATUS/FOG WITH IFR  
CONDITIONS AT TIMES. PERIODS OF RAIN. SLIGHT CHANCE OF  
THUNDERSTORMS WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. E-SE  
WINDS G20KT POSSIBLE ON WEDNESDAY, DAY INTO EARLY EVENING.  
 
THURSDAY: MVFR POSSIBLE WITH A CHANCE OF SHOWERS.  
 
FRIDAY AND SATURDAY: MAINLY VFR, CHANCE OF MVFR AND SHOWERS.  
SLIGHT CHANCE OF THUNDERSTORMS AFTERNOON INTO EARLY EVENING.  
 
DETAILED INFORMATION, INCLUDING HOURLY TAF WIND COMPONENT FORECASTS,  
CAN BE FOUND AT: HTTPS:/WWW.WEATHER.GOV/ZNY/N90  
 
 
   
MARINE  
 
SUB-SCA CONDITIONS ARE EXPECTED ON ALL WATERS THROUGH TUESDAY  
NIGHT. ONSHORE FLOW WILL HELP BUILD SEAS TO 5-6 FT ON THE  
OCEAN WATERS DURING WEDNESDAY ALONG WITH GUSTS AROUND 25 KT.  
WINDS WEAKEN WEDNESDAY NIGHT, HOWEVER A RESIDUAL SWELL SHOULD  
KEEP SEAS AT ADVISORY LEVELS THROUGH THE NIGHT AND INTO A  
PORTION OF THURSDAY. SUB-ADVISORY CONDITIONS THEN FOLLOW FOR  
THURSDAY NIGH THROUGH SATURDAY WITH WINDS REMAINING AT AROUND  
10KT OR LESS.  
 
 
   
HYDROLOGY  
 
RAINFALL FROM TUESDAY AFTERNOON THROUGH WEDNESDAY NIGHT IS EXPECTED  
TO AVERAGE AROUND A HALF OF AN INCH ACROSS THE AREA. NO HYDROLOGIC  
IMPACTS ARE EXPECTED WITH THIS EVENT, AND NO IMPACTS ARE EXPECTED  
THEREAFTER THROUGH MONDAY.  
 
 
   
OKX WATCHES/WARNINGS/ADVISORIES  
 
CT...NONE.  
NY...NONE.  
NJ...NONE.  
MARINE...NONE.  
 
 
 
 
 
SYNOPSIS...BC/JC  
NEAR TERM...BC  
SHORT TERM...BC  
LONG TERM...JC  
AVIATION...JM  
MARINE...BC/JC  
HYDROLOGY...BC/JC  
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