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FXUS61 KOKX 221624
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1224 PM EDT Sat Jul 22 2023

.SYNOPSIS...
Weak high pressure gradually pushes into the region for the
weekend and remains in control through late next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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The forecast is on track with only minor changes needed to account for current observations. Currently, visible imagery depicts a cumulus field building to the north with higher clouds moving in from the south with plenty of breaks. Broad upper troughing remains over the Northeast today, while at the surface, weak high pressure builds in. A cold front remains east of the area and continues to push farther offshore. Seasonable temperatures are expected today. However, a more noticeable change in humidity levels will occur. With a drier air mass advecting in and some mixing of dew points from aloft, dew points will fall into the 50s for much of the area, especially across northeast New Jersey, the Lower Hudson Valley, and New York City. Therefore, more comfortable humidity levels are forecast. These dew points could end up being a few degrees lower depending on the strength of the mixing, which will be dependent on the surface winds.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/... Tranquil weather will continue through the beginning of the new work week as upper level troughing remains in place. A shortwave trough may approach during the afternoon and evening hours on Monday, setting off some showers and thunderstorms, mainly north and west of New York City. With boundary-layer dewpoints a little higher this time, CAPEs will also be higher. It might not take much supplemental mechanical forcing for diurnal convection to pop up as capping appears to be weak. One notable difference among the models is the development of a weak area of low pressure with the ECMWF Monday night that passes just south and east of Long Island. Will have to watch this feature for model run consistency to see if it brings in a period of moderate to heavy rainfall, but for now, much of the precipitation remains offshore. Mostly clear skies and light winds tonight may allow some of the far interior and LI Pine Barrens to drop into the 50s overnight, with the remainder of the region in the 60s. Otherwise, temperatures during the day and night remain seasonable to slightly above seasonable during this time frame. && .LONG TERM /TUESDAY THROUGH FRIDAY/... The pattern much of next week looks a bit more tranquil than recent days, with a relatively flat flow and weak pressure regime. On Tuesday, cyclonic flow from a flattening trough may support some diurnal convection, particularly across the interior, though this looks isolated at this point. The flow aloft appears weak, so only a limited severe wx threat in any pulse-type thunderstorms. WPC currently has a marginal risk for excessive rainfall clipping Orange Co, though any more widespread hydrologic issues look unlikely. The trough axis is progged to shift through during Wednesday, however in a dampened state, maintained a dry forecast for now. Temperatures look to climb mid to late next week as the lifting trough gives way to a building ridge overhead. NBM v4.1 probabilities for Thu and Fri give much of the urban metro over 80% at seeing high temperatures above 90F, though extreme heat appears unlikely at this point. Given a moist S/SW flow, increased dew pts may inflate apparent Ts into headline criteria, though plenty of time to assess this potential. Ridging may start to break down into next weekend, providing a bit of relief from the heat and humidity. Largely followed the national blend of guidance for this update. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... Weak high pressure builds into the region this weekend. VFR through the TAF period. NW flow around 10 kt, right of 310 magnetic, backs W/SW for KJFK/KGON this afternoon. Light NW flow tonight; sea breeze development expected on Sunday. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Winds expected to average right of 310 magnetic for morning and evening push today, except likely backing to the left at JFK for eve push. Low chance of sea breeze reaching KJFK 20Z to 21Z. OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY... Sunday through Sunday night: VFR. Monday: Mainly VFR. Slight chance of a late day shower/tstm KSWF. Tuesday: Chance of afternoon showers/tstms with brief MVFR/IFR vsby from the NYC metros north/west. Wednesday: VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... A Marine Weather Statement is in effect for the Long Island Sound. The National Weather Service in coordination with the United States Coast Guard have received reports of a large debris field across Long Island Sound, caused by recent flooding across New England. This will create some hazards for boaters, swimmers, and watercraft in the affected area. The debris vary from trees, logs, coolers, and docks and may not be easily visible. Sub SCA conditions prevail through the weekend and into early next week with a weak pressure gradient in place. && .HYDROLOGY... No significant widespread rainfall is expected from Saturday through mid next week. && .TIDES/COASTAL FLOODING... There is a moderate risk of rip currents for only eastern Suffolk on Saturday with seas near 3 ft and weak offshore flow, with a low rip risk elsewhere. There is a low risk of rip currents for Sunday, with weak westerly flow and seas less than 3 ft. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP NEAR TERM...JP/BR SHORT TERM...JP LONG TERM...DR AVIATION...DR MARINE...JP/DR HYDROLOGY...JP/DR TIDES/COASTAL FLOODING...