


Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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600 FXUS61 KOKX 182350 AFDOKX Area Forecast Discussion National Weather Service New York NY 750 PM EDT Fri Jul 18 2025 .SYNOPSIS... High pressure moves across the Northeast tonight, then offshore on Saturday. A warm front then approaches Saturday night and passes through the region late tonight into Sunday, followed by a cold front entering late in the day and moving south and east of the area early Sunday evening. High pressure then dominates through Wednesday. A cold front slowly approaches late Thursday through Friday. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... High pressure will be centered to our north tonight with a mostly clear sky and a continuation of relatively comfortable dewpoints mostly in the range of 55-60. This combined with light to calm winds will allow low temperatures to fall into the mid 50s well inland and across the Pine Barrens, with upper 50s to upper 60s for most other locations. As usual, NBM looked too warm for these coolest spots during good radiational cooling conditions, so made some local adjustments. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/... High pressure shifts off the southern New England coast on Saturday, allowing for moisture to increase on a return southerly flow. PVA ahead of a shortwave approaches from the SW in the afternoon, bringing the chance of showers, and with enough CAPE, maybe a thunderstorm too. Showers would be confined to mostly NE NJ, the city, and adjacent areas. NBM looked good for high temperatures. A warm front approaches during Saturday night and is progged to move through part of the forecast area by 12z Sunday. Associated lift with and ahead of the front brings an increased chance of showers and possible thunderstorm to the entire area. Stuck with NBM PoPs, however feel that they could be too low as recent nighttime warm front passages have produced higher shower coverage than what NBM probabilities have implied. The warm front then continues its progress north through the rest of the forecast area during Sunday morning. A trailing cold front then begins to cross the forecast area during the second half of the afternoon. Better overall chances of showers and thunderstorms appear to be with the cold front passage. As for severe weather chances, SPC has the entire area under a marginal risk (5% chance) of severe weather for Sunday. The cold front could be interacting with an airmass with 1000-2000 J/kg SBCAPE. With bulk shear of potentially 30-40kt, unidirectional flow and an inverted-v profile in the boundary layer, strong to severe wind gusts would be possible with thunderstorms. Heat indices on Sunday reach the mid to upper 90s for the NYC metro area, but with just one day of this, no heat advisories would be issued. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... ***KEY POINT*** * Heat and humidity return for the end of next week. An extended period of quite weather is expected during the long term forecast as an upper trough exits the northeast Sunday night with an upper ridge building into Thursday, and then weakening as another shortwave trough moves into eastern Canada and the northeast late Thursday into Friday. At the surface a cold front will be exiting to the south and east early Sunday evening with high pressure dominating into Thursday. A weak surface trough develops inland Wednesday afternoon with a slight chance of precipitation. A stronger surface trough develops for late Thursday into Thursday night with high pressure weakening and shifting south and east. And there will be higher, and more widespread, chances for precipitation. Temperatures will be near seasonal normals Sunday night into Tuesday night, then the heat will build with temperatures above normal Wednesday into the end of the week. Humidity levels will also be increasing beginning Wednesday as a return flow setup up later Wednesday with high pressure moving east of the area. For Thursday and Friday with the combination of heat, with highs in the upper 80s to mid 90s, and humidity, with dew points in the lower 70s, there is the potential for a heat advisory for Thursday and Friday with a 2 day period of heat indices reaching 95 to 103 across much of the area. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... High pressure builds across the area through tonight, then offshore on Saturday. A warm front then approaches Saturday night. VFR through the day Saturday. SHRA/TSRA is possible late in the day Saturday, but coverage and timing varies too much to include in the TAFs, at this time. Better chances occur after 00Z Sunday, so included PROB30 group for -TSRA from 00-06Z Sunday. KEWR and KTEB may see -TSRA a couple of hours earlier. For the metro terminals, NE to NW flow less than 10 kts overnight may become light and variable. There may be an occasional gusts of 15 to 20 kt through 02Z, especially for KLGA. The outlying terminals will likely become light and variable overnight. Winds become S 5 to around 10 kt on Saturday. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No amendments unscheduled amendments expected. .OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY... Saturday Night: Mainly VFR. MVFR or lower in any showers/thunderstorms. Sunday: MVFR or lower in any showers/thunderstorms. Sunday night through Wednesday: VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Sub-advisory conditions expected through Sunday with a weak enough pressure gradient in place. Winds and seas remain below SCA thresholds across the forecast waters from Sunday night through Wednesday night as high pressure dominates. && .HYDROLOGY... Widespread hydrologic impacts are not anticipated through this weekend. However, with precipitable waters values near 2 inches, any thunderstorms could produce brief/locally heavy rain rainfall. Higher overall chances of thunderstorms would be Sunday afternoon, but storms would be moving quickly enough to mitigate a flash flooding threat. There are no hydrologic impacts expected from Sunday night through next week with dry weather much of the time. && .TIDES/COASTAL FLOODING... A moderate rip current risk remains into this evening for the Nassau and Suffolk ocean beaches. The rip current risk for Saturday and Sunday is low at all the ocean beaches with 2-ft southerly wind waves at 4 to 6-sec period and S winds mostly 10 kt or less. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JC/MET NEAR TERM...JC SHORT TERM...JC LONG TERM...MET AVIATION...JP MARINE...JC/MET HYDROLOGY...JC/MET TIDES/COASTAL FLOODING...