Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 301533 AFDOKX Area Forecast Discussion National Weather Service New York NY 1133 AM EDT Fri Sep 30 2016 .SYNOPSIS... The region will remain in between high pressure to the northeast and low pressure to the southwest through the weekend. The low then slowly exits to the east through Tuesday as high pressure builds into the north. This high then continues to build down into the region through the middle of next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Made minor changes with this update to reflect the latest trends in observations and guidance. The forecast appears on track. Unsettled weather will continue through today as a cut off low meanders over the Mid-West while at the same time, a frontal boundary slowly moves north toward the area. Models continue to differ significantly with rainfall amounts. Given that much of what has been on the radar for the past few hours remains either west or south of the area, have continued to lower QPF amounts over the region. Refer to the hydrology section of the AFD for details. It still appears though that rain will move into most if not all the area this afternoon. Gusty NE winds, up to 35 to 40 mph peak gusts near the coast, overcast sky conditions and rainfall will keep things cool and damp. Highs will be a few degrees lower than yesterday, with portions of the Lower Hudson Valley and inland Southern Connecticut not even reaching 60. Generally, upper 50s to lower 60s for high temperatures for the entire area. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/... Chances for rain continue into the short term with the cut off low remaining to the west and the frontal boundary to our south. Again, models differ on exact placement of the heaviest rain. Refer to the hydrology section of the AFD for details. Winds diminish tonight as the pressure gradient relaxes somewhat over the region. Temperatures will be a bit warmer on Saturday, but still a bit below normal for this time of year, generally lower to middle 60s. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... No significant changes made to the long term period as a stagnant and unsettled weather pattern continues for the weekend and into early next week as a stacked cutoff low remains over the Ohio Valley as a ridge over the Western Atlantic remains in place. Models continue to show the upper ridge gradually weakening and shifting south enough early next week to allow the upper low to finally start moving northeast early next week. At the surface, stacked low pressure sits over the Ohio Valley, with a stationary front running northeast from the Mid Atlantic and southeast of Long Island through the weekend. A series of weak waves running along this front will produce periods of rain this weekend. Then as the stacked low finally begins to lift northeast early next week, expect the the main moisture/lift axis to also weaken and lift NE. Lingering scattered showers could continue through early next week via cold pool instability interacting with the maritime air mass. Thereafter, potential for deep layered ridging developing for mid week as the region lies under ridging of an omega blocked pattern. The dry ridged pattern may continue into late week, but will have to monitor the evolution of Hurricane Matthew. Please refer to the National Hurricane Center forecasts for further information. Temperatures will be at or slightly below normal on Sunday, then return to near seasonable for early next week. && .AVIATION /16Z FRIDAY THROUGH TUESDAY/... Terminal area will be in between high pressure to the northeast and low pressure to the southwest today. MVFR continues this morning with potential for IFR visibilities in -SHRA through the day. Highest confidence is ceilings gradually falling, but staying MVFR. Latest thinking is that ceilings may only lower to between 010-015 this afternoon. IFR continues possible overnight. NE winds gusting to 25-30 KT at city/coastal terminals and 20-25 KT at inland terminals. Strongest gusts expected through the middle of the afternoon before slowly diminishing this evening. NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/www.weather.gov/zny/n90 KJFK TAF Comments: IFR visibilities at times in -SHRA through the day. Ceilings are likely to stay 010-015. A gust to 35 kt remains possible. KLGA TAF Comments: IFR visibilities at times in -SHRA through the day. Ceilings are likely to stay 010-015. A gust to 35 kt remains possible. KEWR TAF Comments: IFR visibilities at times in -SHRA through the day. Ceilings are likely to stay 010-015. A gust to 30 kt remains possible. The afternoon KEWR haze potential forecast is GREEN...which implies slant range visibility 7SM or greater outside of cloud. KTEB TAF Comments: Ceilings will gradually fall, but highest confidence in them staying MVFR, 012-018 today. Visibilities should still fall to IFR in -SHRA at times. A gust to 30 kt possible. KHPN TAF Comments: Ceilings will gradually fall, but highest confidence in them staying MVFR, 012-018 today. Visibilities should still fall to IFR in -SHRA at times. A gust to 30 kt possible. KISP TAF Comments: IFR visibilities at times in -SHRA through the day. Ceilings are likely to stay 010-015. A gust to 30 kt remains possible. .Outlook for 12Z Saturday through Tuesday... .Saturday...IFR/MVFR in rain. .Saturday Night-Sunday Night...MVFR or lower possible with showers. .Monday-Tuesday...VFR with isolated to scattered showers possible. && .MARINE... Made minor changes with this update to reflect the latest trends in observations and guidance. The forecast appears on track. Gusts to gale force are expected into this evening on all but NY Harbor, where Small Craft Conditions are expected through tonight. SCA winds are also expected on the remainder of the waters through at least 10z Saturday as well. The strong winds will drive high seas, with seas ranging from 8-13 ft on the coastal ocean waters and from 5-7 ft on the Sound. SCA criteria should continue into mid Saturday morning for the ocean waters, while everywhere else, winds will come down below 25 kt around sun rise. Waves over the Sound will also come down below 5 ft by around sun rise on Saturday. Waves will diminish on the ocean waters as well, but they will remain at or above 5 ft through the day Saturday. Conditions fall below SCA levels Sat night into early Sunday as easterly flow weakens and seas subside. These sub-SCA conditions will remain likely for early next week under a weak pressure gradient. Seas on the ocean waters start to increase mid week with small craft conditions returning. && .HYDROLOGY... There is a high degree of uncertainty on the amount of rainfall through Saturday. 1-1 1/2 inches of QPF possible through Saturday night, with locally higher amounts possible. The prolonged nature of the rain event should preclude any hydrologic issues. No significant rainfall for early to middle portion of next week. && .TIDES/COASTAL FLOODING... Although wind fields weaken by the high tide this evening, widespread minor flooding continues to be a concern for the south shore of Long Island and thus a Coastal Flood Advisory remains in effect for this time frame for Southern Nassau County. Additionally, a persistent easterly sweep of 6 to 10 ft surf today will likely result in minor to moderate beach erosion issues at the the ocean beachfront. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...Coastal Flood Advisory from 6 PM to 10 PM EDT this evening for NYZ179. NJ...None. MARINE...Small Craft Advisory until 8 AM EDT Saturday for ANZ338. Gale Warning until 8 PM EDT this evening for ANZ330-335-340- 345-350-353-355. && $$ SYNOPSIS...BC/JP NEAR TERM...Maloit/JP SHORT TERM...JP LONG TERM...BC AVIATION...JC/DS MARINE...BC/Maloit/JP HYDROLOGY...BC/JP TIDES/COASTAL FLOODING...

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