Area Forecast Discussion
Issued by NWS Upton, NY

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913 FXUS61 KOKX 221955 AFDOKX Area Forecast Discussion National Weather Service New York NY 355 PM EDT MON AUG 22 2016 .SYNOPSIS...
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High pressure will dominate through most of the week. A cold frontal passage is likely on Friday. High pressure will then build into the region for the weekend.
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&& .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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With the upper trough exiting to the northeast into eastern Canada this evening the upper flow becomes zonal tonight, while at the lower and mid levels a ridge builds to the west. At the surface weak cold advection continues into early this evening, then the high builds in and the pressure gradient force and advection quickly weaken. The air will be dry, with lowering dew points, with a cloud free night, and the winds decouple and become light to calm inland, so good radiational cooling conditions set up for tonight. Leaned toward the cooler guidance and lowered temperatures inland and at the normally cooler areas, especially across the Long Island Pine Barrens.
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&& .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
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The ridge continues to build to the west Tuesday and Tuesday night with heights rising through the period. With the strong ridge in place and strong sudsidence, expected to be cloud free. There may be a few CU Tuesday early morning with initial heating of the day. With full sun and good mixing and a weak return flow setting up as the high shifts off shore expecting highs to rebound a few degrees from Mondays highs. Combination of winds shifting to the southwest expect sea breezes to develop. Tuesday night weak warm advection continues with dew points increasing, resulting in higher lows Tuesday night.
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&& .LONG TERM /WEDNESDAY THROUGH MONDAY/...
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The models were in good agreement through the long term, so the Superblend was generally used. High pressure over the east coast on Wednesday will slide offshore on Thursday as a cold front approaches from the west. This will allow for a warming trend Thursday and Friday with an increase in humidity. Scattered showers and thunderstorms are possible with the frontal passage on Friday. Otherwise, some development is possible late Thursday into Thursday night mainly along and west of the Hudson River as the upper ridge begins to break down. A 1020s high pressure system then builds into the northeastern states over the weekend, producing another round of fair weather. There is a hint of some isolated development Sunday afternoon in the ECMWF and to a lesser extent the GFS. It appears to be upslope component terrain induced activity, so this would favor locations just out of the forecast area. As a result, only very low chances for rain have been included in the forecast. A strong shortwave trough then is progged to drop towards the area on Monday. Chances for precipitation have been included in the forecast, but this is so far out they have been limited as the timing of the dynamic feature may be off.
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&& .AVIATION /20Z MONDAY THROUGH SATURDAY/... VFR as high pressure builds over the region. Gusty NW winds around 15 kt with gusts 20-25 kt through much of the day, then diminishing and veering more northerly toward evening. Winds fall below 10 kt tonight. Seabreezes expected during the late morning/early afternoon on Tuesday. NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component fcsts, can be found at: http:/www.weather.gov/zny/n90 KJFK TAF Comments: No unscheduled AMD expected. KLGA TAF Comments: No unscheduled AMD expected. KEWR TAF Comments: No unscheduled AMD expected. KTEB TAF Comments: No unscheduled AMD expected. KHPN TAF Comments: No unscheduled AMD expected. KISP TAF Comments: No unscheduled AMD expected. .Outlook for 18Z Tuesday through Saturday... .Tuesday-Thursday night...VFR. .Friday...Chance of afternoon showers/tstms from the NYC metro terminals and points North and West, with brief MVFR conditions possible. .Saturday...VFR. && .MARINE...
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Winds and seas will remain below small craft advisory levels tonight through Tuesday night as high pressure builds into the forecast waters. There may be occasional gusts to 25 kt across near shore waters into early this evening. Winds and seas are progged to remain below small craft advisory levels Wednesday through Saturday, with high pressure generally in control. There is a suggestion of tropical swell encroaching on the waters Sunday into Monday.
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&& .HYDROLOGY...
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Dry tonight through Tuesday night. Widespread significant precipitation is not expected Wednesday through Monday.
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&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JMC/MET NEAR TERM...MET SHORT TERM...MET LONG TERM...JMC AVIATION...BC MARINE...JMC/MET HYDROLOGY...JMC/MET

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