907 FXUS61 KOKX 270849 AFDOKX Area Forecast Discussion National Weather Service New York NY 449 AM EDT Sun Jul 27 2025 .SYNOPSIS... High pressure moves offshore as a weak frontal system approaches the area this morning. The front heads east of the region tonight into early Monday. High pressure then returns Monday into Tuesday. A cold front approaches Wednesday and moves across the area Wednesday night into Thursday. High pressure builds in from the Great Lakes Friday into next Saturday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... GOES-16 6.95um WV channel depicts a mid/upper shortwave racing through the Great Lakes this morning. A weak N-S oriented surface warm front/trough was located in eastern PA heading east. A moderately unstable airmass east of the frontal feature (MUCAPE 1000- 2000J/kg) was maintain a convective complex with showers and embedded thunderstorms. This activity was generating 1-2.5" of precipitation in central/east PA as it heads east, with rainfall rates between 1-1.25" per hour per latest MRMS. The complex looks to reach the CWA by about 0700-0800Z and should weaken as it does so per SPC mesoanalysis, with a more stable environment as the complex approaches. Much of the day remains cloudy with the warm front hanging around, which will limit overall airmass destabilization. Second round of showers/thunderstorms associated with the approaching shortwave and warm front are likely this afternoon. Model soundings do show an appreciable increase in PWAT, with over 2" by this afternoon along with at least some increase in instability (MUCAPE ~1000J/kg) and shear (0-6km shear values 25- 30kts) with the approaching shortwave. SPC maintains a marginal risk of severe thunderstorms for the parts of area this afternoon as a result. In addition, there is at least a localized flash flood threat this afternoon with any thunderstorms given the high PWAT environment. HREF probabilities of 3" in 3/hr are around 10%, however, further supporting the localized nature of any flash flooding. Any convective activity should weaken as it heads east, given the more stable environment and loss of upper support this evening. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... * Heat and humidity builds on Monday and continues into Tuesday. Heat Advisory in effect for the entire area for both days. Weak upper ridging aloft takes over for Monday and Tuesday as the area continues to reside on the eastern edge of a large upper ridge. An increase in heat and humidity on Monday as weak ridging builds back in behind the departing shortwave. Dry weather is expected. However, h850 temperatures approach 20-21C Monday afternoon with dewpoint in the mid 70s (per NBM). Thus, heat indices of 100-105 for northeast NJ and 95-100 elsewhere look possible once again Monday afternoon. More heat and humidity on Tuesday, under mainly dry conditions, as the upper ridging begins to break down. && .LONG TERM /TUESDAY THROUGH SATURDAY/... The NBM was followed with no changes. Key Points: * Heat and humidity will continue on Wednesday. Widespread heat index values between 95 and 99 with some locations reaching the 100-104 mark. * Chances for showers and thunderstorms increases Wednesday into Wednesday night as a cold front approaches and moves across the region. Showers could persist into Thursday. * High pressure returns to end the week and should dominate the pattern this weekend bringing cooler temperatures and low humidity levels. && .AVIATION /09Z SUNDAY THROUGH THURSDAY/... A weak warm front moves across the region today. Mainly VFR to start, with exception of MVFR visibilities due to haze and smoke from wildfires. Some MVFR conditions will be possible with some showers through about 12z. A period of prevailing MVFR, with a low chance of IFR, will work into the Lower Hudson Valley this morning and then across the remainder of the area during the afternoon hours. VFR conditions are then expected to return Sunday night as drier low-level air filters in behind a surface trough. Light S/SE winds overnight will gradually veer to the S/SW toward morning, increasing to 5 to 10 kt. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments are likely for the timing of showers, possibly thunderstorms, today. There looks to be multiple episodes or rounds. Amendments are also likely for the timing of MVFR or lower conditions on Sunday. .OUTLOOK FOR 06Z MONDAY THROUGH THURSDAY... Sunday Night: VFR or improving to VFR. Monday - Tuesday: VFR. Wednesday: Mainly VFR. A chance of showers and thunderstorms late in the day and at night. Thursday: VFR. A chance of showers with MVFR possible. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... A weak pressure gradient thru Wednesday will lead to the continuation of conditions below Small Craft Advisory levels. Conditions should remain below Advisory levels next Thursday, but there may be a slight increase in winds and seas due to the passage of a cold front. && .HYDROLOGY... Isolated instances of flash flooding are possible this afternoon and evening, mainly for NYC and points N&W. Rainfall rates of 2"/hr are possible. There are currently no hydrologic concerns next week. && .TIDES/COASTAL FLOODING... A low rip current risk overall is expected today and Monday with any onshore swell component a bit weaker and a light southerly wind wave Monday. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for CTZ005>012. NY...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for NYZ067>075-078>081-176>179. Air Quality Alert until midnight EDT tonight for NYZ067>075- 078>081-176>179. NJ...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for NJZ002- 004-006-103>108. MARINE...None. && $$ SYNOPSIS...BC/DBR NEAR TERM...DBR SHORT TERM...DBR LONG TERM... AVIATION...BC MARINE...BC/DBR HYDROLOGY...BC/DBR TIDES/COASTAL FLOODING...