619 FXUS61 KOKX 170836 AFDOKXArea Forecast Discussion National Weather Service New York NY 436 AM EDT Wed Sep 17 2025
.SYNOPSIS... A weak surface low pressure system near the Middle Atlantic coast will slowly track north through tonight. The low will weaken tonight as it pushes south and east of the area through Thursday. A cold front passes across the area Friday. High pressure builds across the Northeast through Saturday and then offshore by Sunday, but maintaining ridging across the area early next week.
&&
.NEAR TERM /THROUGH TONIGHT/... A weak surface low continues to spin near the Delmarva with high pressure ridging remaining over the area. The low will gradually track north and end up lying just off the Jersey coast by this evening. The upper level system supporting the low will flatten and become an open wave tonight allowing the surface low to weaken further and become much broader just south of Long Island.
The main forecast challenge today will be with coverage and northward extent of showers. Dry air and lingering surface ridging from the nearby high pressure has created a corridor that is not supporting the maintenance/development of showers. The NE flow from the high continues to supply subcloud dry air. The low levels should begin to moisten this morning, especially the southern portion of the area as the surface ridging weakens. Probabilities for showers should increase through the morning across the south, but may take some time across the east end closer to the surface high. As the low drifts north this afternoon, bands of shallow convective showers are expected to move in from the south. This process will likely continue tonight with the greatest coverage of showers across the southern half of the area. NBM PoPs look too aggressive and have backed off a bit, especially across the interior and this morning. As the low starts moving east away from the NJ coast, any lingering showers overnight will shift towards the east end of Long Island and southeast CT. The northern half of the area, specifically the interior of the Lower Hudson Valley and interior Southern CT will likely struggle to see showers maintain themselves as they shift inland this afternoon and evening.
The daytime hours are not expected to be a complete washout with showers largely ending up scattered and more periodic. The most likely period for showers will be this afternoon/evening mainly along the coast.
Instability is lacking through tonight, but model soundings indicate some marginal elevated CAPE. Much of this CAPE appears to be above the saturated layer lowest 12kft of the atmosphere. A few isolated lightning strikes are possible, mainly close to the coast this afternoon and evening. Have gone lower than the NBM thunder probs based on sounding analysis and pattern recognition as this system supports mostly shallow convective showers with warm rain processes.
Rainfall amounts overall will be on the light side averaging around a quarter of an inch near the coast and potentially just a few hundredths inland.
Highs today will only be in the upper 60s and low 70s due to cloud cover, easterly flow, and potential showers. Breezy conditions are also anticipated near the coast with potential of gusts around 20 mph through this evening.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... A few showers may linger at the start of Thursday across the east end of Long Island and southeast Connecticut. These should be short- lived as the weak low and dampening shortwave trough push further offshore through the day. Cloud cover may quickly clear into the afternoon behind the departing system which may allow for a fairly quick rise in temperatures. High temperatures in the upper 70s to low 80s are currently forecast based on the quick clearing of clouds in the afternoon. Temperatures may be slowest to rise out east if clouds linger there a bit longer than expected.
A cold front approaches from the NW Thursday night as an anomalously strong upper level trough digs south out of southeast Canada. This will carve out troughing over New England to end the week and send the cold front across the area on Friday. The frontal passage is forecast to be dry and will bring in a cooler, drier airmass for the weekend. Before the front passes, temperatures will warm to above normal levels with much of the area in the upper 70s to lower 80s. A few spots in NE NJ could reach the mid 80s. The cooler air advects into the area Friday night as high pressure starts building in from the north. Lows look to range from the mid/upper 40s inland to the 50s closer to the coast.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/... Key Points:
*High pressure will remain in control through early next week.
*Temperatures will be slightly below normal this weekend, but start trending warmer early next week.
*No precipitation is currently expected.
NBM strictly followed during this forecast period.
Highs will be around 70 for the weekend with an easterly flow on Saturday veering to the SE/S on Sunday as high pressure builds to the east of the area. Lows will generally be in the upper 40s to mid 50s, but closer to 60 for the NYC metro.
A backing upper flow ahead of a trough tracking across the Upper Midwest and Great Lakes Monday into Tuesday will allow for a gradual warmup and increasing humidity. Expect dry conditions to continue during this time but will have to watch the evolution and track of a frontal just off the eastern seaboard.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/... Low pressure meanders just south of the area today before moving east tonight.
09Z TAF update to reflect a later start time of precipitation. Low confidence forecast with respect to when any precip reaches the local region as the precip shield south of the area continues to run into drier air.
Otherwise, VFR at most terminals, with MVFR cigs starting to develop at some terminals. Conditions will continue to fall to MVFR and eventually, some -SHRA will move into the area, mainly mid to late morning. The southern terminals should see the best chance of showers today, while terminals further north will see showers be a bit more spotty in nature, along with some higher cigs. Can not rule out an isolated rumble of thunder, mainly this afternoon, however confidence too low to include in the TAF. Also, can not rule out some IFR cigs this afternoon, however, there is a better chance of IFR cigs tonight, especially for coastal terminals.
ENE or NE winds through the TAF period. Speeds start off around 10 kt or less. Speeds increase to 10 to 15 kt and gusts up to 20 kt possible after sunrise. Winds fall back below 10kt tonight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of flight category changes this morning may be off by a couple of hours.
Gusts may be more occasional on Wednesday.
IFR cigs possible late Wednesday.
.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
Wednesday Night: MVFR or IFR. possible -SHRA.
Thursday: Chance of MVFR/IFR and -SHRA in the morning, especially during the morning push, otherwise VFR.
Friday: VFR. NW gusts around 20kt.
Saturday and Sunday: VFR.
Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE... Persistent E-NE flow with approaching low pressure will continue to provide for SCA conditions on the ocean through this evening. Winds could gust up to 25 kt with seas around 5-7 ft. The low will start moving further offshore tonight and weaken. This should allow seas to subside into Thursday morning. Seas should remain close to 5 ft the first part of tonight and have extended the SCA through midnight. Winds and seas will then remain below SCA levels through Friday evening.
Building high pressure to the north Friday night into Saturday may produce winds around 20 kt on the ocean waters with seas of building to around 4 ft. Winds and seas subside later Saturday and remain below SCA levels through Sunday.
&&
.HYDROLOGY... There are no hydrologic concerns through early next week.
&&
.TIDES/COASTAL FLOODING... There is a high rip current risk at the ocean beaches through this evening due to an easterly swell of 5-7ft at 7-8s and an easterly wind of 15 to 20 kt. The latter of which is also favorable for a strong longshore current. A subsiding swell and an offshore wind less than 10 kt should allow for the risk to lower to moderate on Thursday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...High Risk for Rip Currents through this evening for NYZ075-080-081- 178-179. NJ...None. MARINE...Small Craft Advisory until midnight EDT tonight for ANZ350-353- 355.
&&
$$
SYNOPSIS...DS/DW NEAR TERM...DS SHORT TERM...DS LONG TERM...DS/DW AVIATION...BC MARINE...DS/DW HYDROLOGY...DS TIDES/COASTAL FLOODING...
NWS OKX Office Area Forecast Discussion