


Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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-- Discussion containing changed information from previous version are highlighted. --151 FXUS61 KOKX 152012 AFDOKX Area Forecast Discussion National Weather Service New York NY 412 PM EDT Tue Jul 15 2025 .SYNOPSIS... A weak frontal boundary will remain near the region through the day on Wednesday before lifting to the north Wednesday night. A surface trough moves slowly across the region Thursday followed by a cold front late Thursday night into Friday morning. High pressure builds in Friday and moves offshore Saturday. A warm front moves through the region Sunday followed by a cold front Sunday night into Monday. High pressure builds to the north for Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Outside of a few spotty showers this afternoon, with upper ridging building into the region expecting mainly dry conditions through the overnight. The atmosphere will remain quite moist though, leading to another round of low clouds and patchy fog overnight. With plenty of cloud cover, low temperatures will only fall to around 70 in typically cooler locations and to the mid 70s in the New York City metro area. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... Upper ridging moves offshore during the day as a shortwave approaches the region from the southwest before crossing the area Wednesday night. Low clouds and patchy fog to start the day should give way to gradual clearing by mid to late morning before clouds quickly return ahead of the approaching shortwave. The abundance of clouds may help limit temperatures somewhat, but with dewpoints in the mid 70s, heat index values will rise into the mid to upper 90s across the majority of the area. With hot and humid conditions continuing on Thursday, a Heat Advisory has been issued for the entire region with the exception of eastern Suffolk County. The approaching shortwave will spark scattered convection by late afternoon for locations west of NYC, gradually translating eastward across the rest of the area through the overnight hours. While the overall severe threat remains minimal, with precipitable water values at or above 2 inches any showers and storms will be capable of producing heavy rain and localized flash flooding. The flooding threat may be locally maximized across portions of northeast New Jersey and the Lower Hudson Valley given the wet antecedent conditions, but confidence in the location of any heavier rainfall remains too low for a Flood Watch at this time. && .LONG TERM /THURSDAY THROUGH TUESDAY/... ***Key Points*** * Heat and humidity continues for Thursday with a Heat Advisory in effect for most of the region. A few locations across northeastern New Jersey may reach heat indices around 105 Thursday afternoon. * Showers and thunderstorms likely Thursday ahead of a cold front. Dry conditions return Friday and Saturday. The peak of the heat and humidity will likely occur during Thursday with heat indices across all but the Twin Forks of Long Island reaching into the upper 90s to 100 to 104. A few locations across northeastern New Jersey may peak at around 105, which is Heat Warning levels. However, with extensive cloud cover, and showers and thunderstorms becoming likely during the afternoon, confidence in reaching these heat index levels is low, therefore a Heat Warning was not issued at this time. Also, the timing of the cold front has increased, with the passage now late Thursday night into Friday morning. And with the quicker timing of the passage drier air will be moving into the region, so despite the continued heat, peak heat indices will likely fall below advisory levels. With high precipitable water values of 2 to 2.25 inches Thursday and showers and thunderstorms have the potential of producing heavy rainfall, with the threat of localized flooding. High pressure builds into the region for Friday and moves offshore Saturday. The cold front that moved through Friday morning remains south of the region, and possibly moves into a portion of the region Sunday before stalling as high pressure passes well to the north. Another cold front passes Sunday night into Monday, and may stall near the region into Tuesday. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... A weakening frontal boundary nearly stalls within the region through Wednesday. There could be some additional pop-up showers in the vicinity of some terminals into early this evening. Otherwise VFR conditions expected through early this evening for most terminals. Then, for latter half of this evening, overnight into Wednesday morning, low clouds and fog redevelop with a variance of conditions across the region, mainly east of NYC terminals. There will be increasing potential for MVFR to IFR. Then, for Wednesday once the low clouds and fog decrease, VFR conditions prevail again until showers and thunderstorms develop mid afternoon into early evening Wednesday, presenting again another chance for MVFR to possibly IFR conditions. Winds overall mainly out of the south near 5-10 kts for much of the TAF period. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments possible for brief thunderstorm before 22Z. Amendments likely to refine timing of fog overnight into early Wednesday morning. IFR possible for early Wednesday. .OUTLOOK FOR 18Z WEDNESDAY THROUGH SATURDAY... Wednesday-Thursday: MVFR or lower in any afternoon/evening showers/thunderstorms. Friday-Saturday: Mainly VFR. Sunday: MVFR or lower with showers and possible thunderstorms. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Sub-SCA conditions are expected through Wednesday night, with winds generally remaining under 15 kt and seas remaining under 3 ft on the ocean. Winds and seas across the forecast waters remain below advisory levels Thursday. However, with an increasing and persistent southwest flow ahead of an approaching cold front a few gusts may be near SCA and ocean seas will be building and may approach 5 feet late in the day. And by Thursday evening ocean seas, mainly east of Fire Island Inlet, will build to SCA levels. With the passage of the cold front late Thursday night into early Friday morning seas will subside below advisory levels. Conditions will then remain below advisory the remainder of Friday through Sunday night. && .HYDROLOGY... Localized flash flooding will be possible from scattered afternoon and evening convection on Wednesday. Hydrologic impacts are not expected Thursday through early next week. && .TIDES/COASTAL FLOODING...-- Changed Discussion --The risk for the development of rip currents remains low into this evening. The low risk will remain Wednesday as a light southerly flow continues with around 2 foot waves. With a strengthening southwest flow Thursday, the risk for rip current development will be moderate. Waves will be 2 to around 3 feet.-- End Changed Discussion --&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for CTZ005- 009. Heat Advisory from 11 AM Wednesday to 10 PM EDT Thursday for CTZ005>012. NY...Air Quality Alert from 11 AM to 11 PM EDT Wednesday for NYZ069>075-176-178. Heat Advisory from 11 AM Wednesday to 10 PM EDT Thursday for NYZ067>075-078-080-176>179. NJ...Heat Advisory from 11 AM Wednesday to 10 PM EDT Thursday for NJZ002-004-006-103>108. MARINE...None. && $$ SYNOPSIS...FEB/MET NEAR TERM...FEB SHORT TERM...FEB LONG TERM...MET AVIATION...JM MARINE...FEB/MET HYDROLOGY...FEB/MET TIDES/COASTAL FLOODING...MET