874
FXUS61 KOKX 120221
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1021 PM EDT Sat May 11 2024

.SYNOPSIS...
A frontal system approaches from the west tonight and then
passes south and east of the area on Sunday. High pressure
returns Sunday night. A warm front passes north of the area
Monday into Tuesday. Low pressure may impact the area for the
middle of the week, with another frontal system possible by next
weekend.

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.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
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Only minor changes were made for the current conditions. Slightly lowered probabilities with the slower onset of showers into the overnight. A large upper level trough remains over Eastern North America. Within this trough, a middle level ridge will push east of the area tonight, followed by a shortwave trough. At the surface, high pressure continues to ridge down from northern New England. The approaching shortwave continues to bring increased cloud cover into late tonight. An associated frontal system will slowly approach with lift increasing west of the NYC metro between around 03 and 06z. Showers will accompany the increased lift, especially across NE NJ and the Lower Hudson Valley, slowly making their way towards the NYC metro around day break. Mainly light showers are expected with a small chance for a brief occurrence of moderate intensity. A chilly night is in store despite the increasing cloud cover. Lows look to fall into the middle and upper 40s for most spots and around 50 degrees in the NYC metro. These low temperatures range from 5-10 degrees below normal for this time of year.
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&& .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... The aforementioned shortwave becomes a broad closed low overhead early Sunday morning. There will be two separate areas of middle level energy within the low, one to our northeast and then another to our south and west. The models are also in good agreement with the cutoff low quickly shifting to our east around midday. The remaining energy to our south and west will shift to a less favorable position for supporting the shower activity. The upper trough and cutoff low will then slowly shift to a position near or just off the New England coast Sunday evening. Showers, mainly on the light side, will continue from around the NYC metro/Hudson River corridor in the morning. The showers will try to shift eastward in the morning, but will likely encounter subsidence behind the lead energy and slowly dissipate as they move over southern CT and western/central Long Island. The showers will continue to dissipate early in the afternoon with dry conditions likely returning around 19z. Total rainfall amounts range from one to two tenths west of the NYC metro, a few hundredths to a tenth in the NYC metro, and possibly a trace to see a few hundredths east of the Hudson and NYC metro. Locations on the east end and southeast CT may remain completely dry. Lingering middle level moisture likely leads to mostly cloudy skies for the remainder of the daytime hours. The other story for Sunday will be unseasonably cool temperatures with highs only reaching the middle and upper 50s. These highs are 10-15 degrees below normal for this time of year. Heights will rise Sunday night as the upper trough continues departing to the east. Surface high pressure will be in place leading to dry conditions. Clouds should slowly diminish through the night with mostly clear to partly cloudy skies by early Monday morning. Another chilly night is expected with lows in the 40s. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... Dry wx is expected on Mon with high pres along the coast. Sly flow develops during the day with a warm front to the N and sea breeze impacts. This will modify temps for most of the area E of the Hudson River. With the boundary to the N and some energy embedded in the flow aloft, a few shwrs are possible Mon ngt and Tue. Greater instability could yield some tstms N and W of NYC Tue aftn and eve, then low pres approaches from the SW and rain, with a few embedded tstms, overspreads the area Tue ngt into Wed. Despite the cool ocean, the warm airmass yields highs in the 60s and 70s on Tue per the NBM. Mixing down the GFS from h85 would produce mid 70s without adding in the seasonal solar adjustment which would bring the numbers to around 80. Stuck with the NBM for now, but some higher readings possible in NJ and up the wrn portion of the Hudson Valley. Clouds and residual rain keep temps lower on Wed, then pcpn chances subside Wed ngt into Thu. Temps rebound on Thu with more sunshine despite nely flow. Another frontal sys is possible late Fri into Sat. The timing and track are a little uncertain, with the ECMWF slower than the GFS. As a result, the blended approach using the NBM was used. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/...
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Weak high pressure along the Maine coast and extending into the mid Atlantic coast will slowly give way to an approaching weak frontal system overnight into early Sunday. The frontal system weakens Sunday while passing to the south. Mainly VFR through tonight with a chance of showers late. Patchy MVFR clouds around 2500 feet have developed across Long Island and were moving into southern Connecticut, so MVFR ceilings will be possible at times at KISP, KBDR, and KGON. Then becoming widespread MVFR soon after sunrise at the NYC metro terminals and west with showers likely, and a chance of becoming MVFR with a chance of showers east. MVFR with a chance of showers will remain at the NYC metro terminals and west late morning into around mid afternoon as the frontal system slowly weakens, then becoming VFR. A brief period of IFR can not be ruled out at KSWF and KTEB early Sunday morning. Dry conditions are likely through the forecast at KGON. A light S to SE flow continues through the forecast, becoming light SW Sunday night. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled AMD expected until toward Sunday morning for timing of developing MVFR and showers. OUTLOOK FOR 00Z MONDAY THROUGH THURSDAY... Sunday night through Monday: VFR. Tuesday: MVFR or lower possible in mainly afternoon showers, an isolated thunderstorm possible inland. S winds 15kt coastal terminals. Tuesday night: MVFR likely in showers and possible tstms. S winds 10-15kt coastal terminals. Wednesday: MVFR or lower still likely in showers and t-storms. SE winds 10-15G20kt, becoming NE late day and at night. Wednesday night: VFR. N winds 10-15G20kt. Thursday: VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
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&& .MARINE... No changes to the winds and seas at this time. Seas east of Moriches Inlet are likely to end up around 4 ft this evening and may occasionally reach 5 ft. Not anticipating the need for an SCA. Conditions will remain below SCA levels through Tuesday night with a weak pressure gradient over the waters. There could be period of marginal 5 ft seas on the ocean Mon and Tue. A SCA will be needed on the ocean Wed with low pressure, and possible elsewhere. SCA cond may linger through Thu, subsiding by Fri. && .HYDROLOGY... No hydrologic impacts expected through next week. && .TIDES/COASTAL FLOODING... Only localized minor coastal flooding is expected for the most vulnerable locations along the south shore back bays of Nassau County with high tide tonight. A coastal flood statement remains in effect. Otherwise, no additional coastal flooding is anticipated as astronomical tide levels continue subsiding into early next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JMC/DS NEAR TERM...DS/MET SHORT TERM...DS LONG TERM...JMC AVIATION...MET MARINE...JMC/DS/MET HYDROLOGY...JMC/DS TIDES/COASTAL FLOODING...