880
FXUS61 KOKX 251403
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1003 AM EDT Sat May 25 2024

.SYNOPSIS...
High pressure today will give way to a weakening frontal system
this evening into early Sunday. A surface trough lingers nearby
on Sunday. A stronger frontal system will impact the area
Monday into Monday night with a series of fronts following it
Tuesday into Wednesday. An upper level disturbance may impact
the area towards the end of next week.

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.NEAR TERM /THROUGH TONIGHT/...
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Weak high pressure over the area this morning will shift offshore this afternoon. An upper ridge axis will also slide across New England. A flat middle level shortwave quickly follows this evening into tonight, which will bring a weakening frontal system into the area. It will remain dry through early this evening as subsidence lingers due to the aforementioned ridging. There will be increasing middle and high level clouds with the approaching shortwave, especially in the afternoon and evening. Highs will be above normal with rapid heating this morning, ranging from the mid to upper 70s near the coast to the lower and middle 80s in the NYC metro and areas to the NW. Hybrid seabreeze/SE synoptic flow will push well inland today, likely capping temp rise in the early to mid afternoon for much of the coastal plain. Immediate south coastal locations will likely hold temps in the upper 60s to lower 70s with onshore flow already developing. A broken line of showers should be approaching from the NW this evening in association with the shortwave and weakening front. CAMs all show this line weakening as it enters the NW interior sometime between 7pm-10pm. There is only a marginal amount of CAPE aloft and the latest forecast soundings indicate a lingering middle level cap. For these reasons, have left mention of thunder of the forecast. Otherwise, a low chance PoP exists initially this evening over western Orange County with a slight chance slowly making its way east through the night. Surface convergence along the front may be able to generate a few showers overnight as the boundary washes out or stalls over the region. This is due to the shortwave flattening and heights beginning to rise towards early Sunday morning. Lows will be in the upper 50s and lower 60s.
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&& .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... The lingering boundary becomes difficult to discern Sunday morning and the latest guidance is indicating that it should largely become a surface trough by afternoon. A lingering isolated shower is possible in the morning. The trough likely retrogrades inland in the afternoon with the development of sea breezes. Ridging builds aloft, so there is not any significant forcing for organized convection. The convergence along the surface trough may be enough to trigger a shower or thunderstorm in the afternoon and early evening well north and west of the NYC metro. Forecast soundings show more instability, but there will likely be a cap around 5 kft, limiting organization. Sunday may be a bit more humid compared to Saturday with similar temperatures. Any early evening convection dissipates with loss of heating. Attention will then quickly turn to the next shortwave and associated low pressure over the midwest. This system will send a warm front north of the area late Sunday night into Monday morning aiding in increasing chances for showers and possibly a thunderstorm. The system will draw in a stronger onshore flow component, which will limit surface instability with the warm front. The low pressure will continue deepening as it moves through the Great Lakes on Monday and then into southeast Canada Monday night. The low will bring a deeper moisture feed with PWATs reaching 1.50- 1.75 inches Monday afternoon into Monday night. The associated cold front should begin entering the area from the west late in the day and then move across the rest of the region Monday night. There is potential for multiple rounds of showers and embedded thunderstorms along and ahead of the front. The overall system should remain progressive, which will limit the flooding potential. WPC has continued to highlight portions of NE NJ and the Lower Hudson Valley in a slight risk for excessive rainfall. This area has a bit higher chance at seeing heavier rainfall which could lead to flash flooding. Elsewhere, the risk is marginal with an isolated flash flood risk. The modest onshore flow and abundant cloud cover will limit instability and any severe thunderstorm risk. Average rainfall amounts range from around a half to three quarters of an inch east of the Hudson River and NYC metro to around one inch west of NYC. Locally higher amounts are possible. Showers and embedded thunderstorms will continue pushing offshore late Monday night into early Tuesday morning. The cold front may linger over eastern Long Island and southeast Connecticut as the upper trough remains well to the west. However, the deep moisture feed will likely be located offshore. && .LONG TERM /TUESDAY THROUGH FRIDAY/... Not much change in the long term and stuck fairly close to the previous forecast/NBM. A cold front exits the area Tuesday morning with what should be mainly a dry day. Another shortwave/cold front is expected to move across the area on Wednesday. There are some timing issues with this second cold front, which could become significant in how quickly the airmass can destabilize ahead of an approaching cold front on Wednesday. For now, will cap POPs at chance and will mention scattered convection. For the end of the week, high pressure builds in on Thursday, but this will depend on how quickly the energy exits to the east and there are differences. The 00Z ECMWF continues to cut off an upper low across the area by Friday. This could result in clouds and showers each afternoon. Temperatures do cool down a bit at the end of the week, closer to normal, but with an amplifying upper trough an/or closed low, this may start trending down. The warmest day of the week will be Tuesday, with highs in the upper 70s and lower 80s for much of the area. lower to middle 70s can be expected closer to the coast. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... High pressure remains in control today. A weakening disturbance approaches tonight into early Sunday morning. VFR through the TAF period. Light and variable (mainly onshore) winds expected through early morning. The winds then become SE-S by afternoon with coastal terminals getting to around 10 kt. Winds become light once again tonight. There will be a chance of some sub-VFR cigs in showers possible after 06z Saturday. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled amendments expected today. OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY... Sunday: Morning IFR/MVFR possible coastal terminals...otherwise VFR. Monday: Chance of showers and possibly a tstm, with MVFR cond possible. Tuesday: VFR. Wednesday: Chance of showers and possibly a tstm, with MVFR cond possible. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... A weak pressure gradient and lack of significant swell will lead to conditions below SCA levels through Sunday night. A strengthening S-SE flow on Monday could into result in marginal SCA conditions on the ocean waters, mainly late in the day into the first half of the night. Winds and seas will generally remain below SCA criteria for the middle and end of the week, however with thunderstorms possible over portions of the waters especially Tuesday and Wednesday, there will be a chance of brief SCA conditions in the storms. && .HYDROLOGY... A frontal system Monday into Monday night may bring several rounds of moderate to heavy rainfall. There remains uncertainty with the axis of heavy rainfall, but chances remain highest for heavier rainfall across NE NJ and the Lower Hudson Valley. This is where WPC continues to highlight a slight risk for excessive rainfall and a bit better chance for scattered flash flooding. The risk is marginal elsewhere with just isolated flash flood potential. && .TIDES/COASTAL FLOODING...
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A southerly flow at 5-10 kt and a southerly swell of 1 ft 8-9s should keep the rip current risk low through Sunday. This continues to be supported by latest RCMOS at area beaches. The rip current/longshore current risk will likely increase to moderate through the afternoon Monday as E/SE winds strengthen and SE wind waves build to 3 to 4 ft.
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&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...BC/DS NEAR TERM...DS/NV SHORT TERM...DS LONG TERM...BC AVIATION...JC MARINE...BC/DS HYDROLOGY...BC/DS TIDES/COASTAL FLOODING...