000
FXUS61 KOKX 261950
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
350 PM EDT Fri May 26 2023

.SYNOPSIS...
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High pressure will continue building in from the Great Lakes going into this holiday weekend. The high pressure area will begin to weaken and shift offshore towards the latter half of the holiday weekend. A backdoor cold front likely moves through during Monday afternoon into evening. High pressure otherwise remains in control through Thursday with another cold front passing through during Friday.
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&& .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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Going into tonight with the thermal trough dissipating as temperatures cool, pressure tendency increases, allowing for subsidence. Surface high pressure will build in more tonight with ridging aloft. As a result, winds decouple, become lighter, and sky conditions will remain mostly clear. This will provide ideal radiational cooling conditions. For the forecast lows tonight, used a blend of 3/4 of the relatively cooler MAV MOS and 1/4 of the relatively warmer MET MOS with a more vast range of temperatures from the upper 30s in the Pine Barrens of Long Island to upper 50s within parts of NYC.
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&& .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
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Aloft in the mid levels, continued ridging takes place along with negative vorticity advection Saturday into Saturday night. The ridging begins to break down in the mid levels Saturday night into Sunday. High pressure at the surface overall will still be in control with dry conditions continuing. For Saturday, high pressure will continue to remain in control with its center moving across the region. The weakness in the pressure gradient will keep winds light and allow for sea breeze circulations to easily develop during the afternoon. More southerly flow is expected during the afternoon but winds remain relatively light, around 10 mph or less on average. Winds will be relatively higher along the coast compared to farther inland. Subsidence from the high pressure will still be evident with mostly sunny conditions. The vertical mixing will be less than that of the previous day. With model 850mb temperatures trending a few degrees higher compared to the previous day, surface temperatures will likewise be trending warmer compared to the previous day as well. The limited vertical mixing and sea breeze will counter some of the warming trend but still the net result will be warmer temperatures compared to those of Friday. The forecast highs are are a blend of NBM as well as MAV and MET MOS, ranging from near 70s for eastern coastal locations, to the upper 70s across much of the interior including Northeast NJ and much of NYC. For Saturday night, high pressure remains strong but becomes positioned more offshore, allowing for a prevalence of very light southerly flow. Also, the high pressure area loses a little strength going into early Sunday morning. The subsidence from the high will keep clouds a low coverage and with the winds being light, radiational cooling will be nearly optimized once again. Forecast lows were a blend of MAV and MET MOS guidance, ranging from the lower 40s in the Pine Barrens of Long Island to near 60 for parts of NYC. For Sunday, high pressure will continue to weaken and will remain based offshore. The will allow for a slightly stronger southerly flow to develop with the enhancement from the sea breeze circulation development. Coastal locations will have more in the way of gusts, getting up to around 20 mph, develop during the afternoon. With less subsidence, also expecting clouds to have a greater presence during Sunday, especially by mid to late afternoon. As a whole on average though, another mostly sunny day is expected. Model 850mb temperatures continue to warm up a few degrees compared to Saturday. This warming trend will be mitigated at the surface due to the sea breeze and some extra clouds along the coast so high temperatures here will not be too different from those of Saturday. However, for inland as well as Northeast NJ and NYC more of a warming trend is forecast, with forecast highs in the mid 70s to upper 70s with some locations reaching near 80.
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&& .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
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The long term period will be dominated by an anticyclonic flow aloft and high pressure at the surface, but a couple of cold fronts are expected to pass through. The first of which is anticipated on Monday afternoon as a backdoor cold front drops down from the north. This will bring somewhat breezy conditions with a shot of cold air advection. Inland high temperatures should still be able to sneak into the 80s before the onset of cold advection, but coastal areas are likely held in the 70s as the easterly wind flow ushers in cool air from the ocean and LI Sound waters. Additionally, the front will be passing through with little moisture, so dry weather is anticipated. Remaining dry for at least Tuesday through Thursday with highs on Tuesday at or slightly below normal. Highs then moderate Wednesday and Thursday, with Thursday`s highs possibly reaching 90 for some inland spots. Dewpoints on Thursday will be only in the 50s, so heat indices will be at or below ambient temperatures. The next cold front passes through sometime on Friday, although the part of the day in which the front passes through is uncertain. Based on NBM PoPs and QPF fields from the global models, will leave in a slight chance of showers Friday afternoon into Friday evening. Highs primarily in the 80s across the area with some 90s inland. No heat advisory concerns due to dewpoints in the 50s again.
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&& .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... VFR as high pressure remains in control through the weekend. Northerly flow and deep mixing will likely delay the seabreeze to late afternoon/early evening for the coastal terminals. Elsewhere, N winds will generally be at 10 kt or less with occasional gusts 15-18kt early. Winds will then go light and variable tonight, becoming light NE after 12Z Saturday, then SE by afternoon at 10 kt or less. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Timing of seabreeze could be delayed by 1-2 hours. OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY... Saturday-Wednesday: VFR. E winds G15-20kt Monday and Tuesday. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE...
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With the pressure gradient remaining relatively weak overall, conditions on all forecast marine zones are expected to remain below SCA thresholds through much of the holiday weekend. A cold front passes through the waters Monday afternoon. With a shot of cold air advection and a tightening pressure gradient, gusts to 25 kt will be possible on most waters during the afternoon and evening. Additionally, an easterly wind may build seas up to 5 ft on the ocean during Monday night. After possible lingering SCA conds on the ocean Tuesday morning, sub-advisory conds continue thereafter through Wednesday as an onshore wind weakens to below 15 kt.
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&& .HYDROLOGY... The prolonged stretch of dry weather continues through the entire forecast period. && .TIDES/COASTAL FLOODING...
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There is a moderate risk of rip current development today with 3-4ft@9 sec period ESE swell, enhanced by afternoon SE sea breeze development. A moderate risk of rip current development on the ocean waters is likely to continue Saturday through Monday.
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&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JC/JM NEAR TERM...JM SHORT TERM...JM LONG TERM...JC AVIATION...DW MARINE...JC/JM HYDROLOGY...JC/JM TIDES/COASTAL FLOODING...