


Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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797 FXUS61 KOKX 061819 AFDOKX Area Forecast Discussion National Weather Service New York NY 219 PM EDT Sun Jul 6 2025 .SYNOPSIS... High pressure remains offshore into Monday. Weak low pressure passes nearby Monday afternoon into Monday night. A cold front approaches Tuesday and moves over the area Tuesday night. The front likely stalls nearby the rest of the week leading to unsettled conditions, potentially into next weekend. && .NEAR TERM /THROUGH TONIGHT/... Warm and increasingly muggy conditions are expected tonight as high pressure remains offshore. SW flow will advect increasingly higher dew points through the night and help increase lower level moisture. Some fog is possible overnight, especially the eastern half of the area and close to the coast. There should otherwise be increasing clouds through day break Monday. Conditions will remain dry as there is no forcing for any showers through day break. Lows will be in the upper 60s inland to lower and middle 70s near the coast. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... Key Messages... *Showers and possible thunderstorms late Monday morning into Monday evening, especially in the vicinity of the NYC metro, NE NJ into Lower Hudson Valley, could produce locally torrential downpours. Localized flash flooding is possible from any of these showers/storms. *Warm and humid conditions Monday and Tuesday with max heat indices in the lower 90s Monday and mid to upper 90s on Tuesday. *Showers and thunderstorms possible Tuesday afternoon and evening with a continued chance of locally heavy downpours. The main concern on Monday will be the development of showers and possible thunderstorms late morning into the afternoon. The extratropical remnant circulation of Chantal will likely track over the Delmarva in the afternoon and then offshore Monday evening and night. It should be emphasized that the circulation will no longer be tropical, but leftover tropical moisture will be present across the northeast. This moisture will act on the sea breeze boundary as well as some middle level energy to promote the development of showers and a few thunderstorms. PWATs are quite high and range from 2-2.25 inches. There is some question to the amount of instability, but model soundings indicate a long and relatively skinny CAPE, which is common in more tropical air masses. Freezing levels look to average around 15kft as well, supportive of efficient/warm rain processes. The 12z CAMs all signal convective development across portions of NE NJ into the Lower Hudson Valley, potentially into the NYC metro. Elsewhere, showers are possible but coverage looks to be lower and could just be isolated. No flood watch has been issued at this time, but WPC has placed NE NJ, NYC metro, and Lower Hudson Valley in a marginal risk for excessive rainfall. Basin averaged rainfall amounts around one quarter of an inch possible with some local areas receiving 1-2 inches with higher amounts. Some locations may see little to no rainfall through Monday evening. Focus for showers shifts to the eastern part of the area Monday night with the weak wave of low pressure passing to our south. It appears most of the coverage should be offshore, but cannot rule out some showers or isolated thunderstorms across portions of Long Island or even southeast Connecticut. For Tuesday, a cold front slowly approaches from the north and west. Ahead of the front, tropical moisture will linger with PWATs around 2 inches. Showers and thunderstorms are likely to develop in the afternoon and evening along and ahead of the cold front from the NYC metro on NW. This activity will then slide eastward in the evening and at night. The main concern from this activity will once again be torrential downpours and localized flash flooding. WPC continues to place the entire area in a marginal risk for excessive rainfall on Tuesday. An isolated severe thunderstorm is possible Tuesday afternoon/evening and SPC has much of the area in a marginal risk. No heat advisories have been issued at this time for Monday and Tuesday. Temperatures have continued to trend slightly lower for Monday, likely due to increasing cloud cover and earlier timing of convection. Highs looks to range from the middle to upper 80s with max heat indices in the lower 90s. It will be warmer on Tuesday as highs should be in the upper 80s to lower 90s. There is still some question to the amount of cloud cover and how high dew points will be in the warmest part of the day. There are hints at the flow becoming more SW-W which could lower dew points a bit. Heat indices should be higher, in the middle to upper 90s. Have held off on the issuance of a heat advisory for Tuesday since this is just one day occurrence and there is little to no coverage of heat indices above 100. The front moves over or just east of the area Tuesday night. The front may begin stalling nearby, which could promote continued showers/storms for the eastern half of the area. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... The NBM was generally followed given the unsettled nature of the pattern for the extended period. A stalled front south of the area on Wednesday will remain in the general vicinity through the end of the week and into the weekend. High pressure over the western Atlantic will allow for the persistent advection of moisture over the front and into the area through much of the week. This will lead to the development of scattered showers and storms through much of the middle and end of the week, though storms are generally more likely in the afternoon and early evening hours with the presence of daytime heating. Additional energy in the flow approaches the area by the end of the week and may result in another round of showers and storms, though guidance has been backing off on high pressure building in thereafter. Unsettled conditions may persist through the weekend. Despite the ample cloud cover and general unsettled conditions this week, temperatures should be right around average for this time of the year with highs each day in the low to middle 80s. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... High pressure this afternoon weakens tonight and Monday as a weak wave of low pressure approaches from the south. VFR through this evening with mostly MVFR/IFR developing overnight. Improvement back to mostly VFR on Monday, however showers with a chance of thunderstorms starting at around noontime bring lower flight categories. S-SW winds 10-15kt with gusts around 20kt bcmg more southerly tonight and diminishing. Winds pick up from the south on Monday, increasing back to 10-15kt with possible gusts around 20kt. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Gusts today may be only occasional. .OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY... Monday through Friday: Primarily VFR each day with mainly afternoon and evening showers/tstms possible with MVFR or IFR cond. Highest chance exists from late Mon through Tue evening. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... A few gusts close to 25 kt are possible on the ocean this afternoon/evening. Otherwise, conditions will remain below SCA levels on the waters through Monday. Seas begin building Monday night into Tuesday and may approach 5 ft east of Moriches Inlet into Tuesday night from a SE swell. Generally weak flow will result in sub-SCA conditions on all waters through at least Friday. && .HYDROLOGY... Locally torrential downpours are possible late Monday morning into Monday evening, especially across NE NJ, NYC metro, and Lower Hudson Valley. This activity could produce localized flash flooding and WPC has this area in a Marginal risk for excessive rainfall. The risk for locally torrential downpours and localized flash flooding remains possible on Tuesday for the entire area. WPC has maintained a marginal risk for excessive rainfall for Tuesday. && .TIDES/COASTAL FLOODING... The rip risk for all beaches will be moderate both today and Monday, given the southerly flow and increasing southerly swell. Surf heights around three ft are likely over the period, but may increase to near 4ft by Monday, especially across NYC, Nassau and western Suffolk beaches. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Air Quality Alert until 11 PM EDT this evening for CTZ005-009. Air Quality Alert from 11 AM to 11 PM EDT Monday for CTZ005- 009. NY...Air Quality Alert until 11 PM EDT this evening for NYZ069>075- 176-178. NJ...Air Quality Alert until 11 PM EDT this evening for NJZ002-004- 006-103>108. MARINE...None. && $$ SYNOPSIS...DS/MW NEAR TERM...DS SHORT TERM...DS LONG TERM...MW AVIATION...JC MARINE...DS/MW HYDROLOGY...DS/MW TIDES/COASTAL FLOODING...