Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 221113 AFDOKX Area Forecast Discussion National Weather Service New York NY 713 AM EDT Sat Oct 22 2016 .SYNOPSIS... Deepening low pressure will track north across coastal New England today and then into eastern Canada tonight into Sunday. Another cold front will move southeast across the area early Monday morning followed by Canadian high pressure through Wednesday. Low pressure will move slowly east toward the area Thursday through Friday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Cold front has worked as far east as far eastern LI and southeast CT and will clear the area in the next hour. Latest radar imagery indicates widespread showers from NYC and points north and west. with widely scattered to the east. The intensity has weakened over the last couple of hours with rainfall rates less than a tenth of an inch an hour. This area will continue to work north this morning and gradually pivot NE as a negatively tilted upper trough approaches from the west. This combined with a steeply sloped frontal surface will produce deep- layered post-frontal lift that translates slowly east with time. Showers will work east across LI and CT this morning. Conditions will begin to gradually dry out this afternoon as the upper low passes to the north. More importantly though, will be strong west winds on the backside of deepening low pressure across coastal New England today. Pressure rises this afternoon and tightening of the pressure gradient will result in the potential for gusts up to 50 mph across LI/NYC/SE CT, and 35 to 40 mph elsewhere. The top of the mixed layer approaches 50 kt near the coast late this afternoon. It always a tough question as to how much of this mixes down to the surface, but strong cold advection and decent pressure rises support a high percentage of these winds transferring down to the surface. Some of the higher elevations across the Lower Hudson Valley and NE NJ may even experience occasional gusts up to 50 mph as well. A wind advisory remains in effect for NYC/Long Island/SE CT, where the highest pressure rises occur this afternoon into early this evening. In addition, the highest sustained winds are expected across the coastal sections, maximizing offshore of Long Island. High temperatures will occur around daybreak and then gradually fall today into the upper 40s and lower 50s. Most locations by afternoon will be 10 degrees below normal.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... Any leftover showers tapper off from south to north tonight as moisture and forcing lift northward with the low. Gusty west winds up to 50 mph, strongest at the coast, will continue as the low slowly lifts to the north. Wind advisory remains up overnight for LI/NYC/SE CT. Winds during the day on Sunday will gusts up to 40 mph for most locations. Upper trough lifts across eastern Canada on Sunday with a gradually weakening surface low. High pressure builds east across the southeast. Lows tonight will be near seasonable levels as gusty winds inhibit strong radiational cooling. Highs on Sunday rebound to near normal with highs in the mid 50s to lower 60s. Clipper low approaches Sunday night and sends a cold front through the area by daybreak Monday. There is decent lift in the 85h-500h layer with a good chance of showers. && .LONG TERM /MONDAY THROUGH FRIDAY/... Monday through Wed will be quite cool as a building canadian high pressure system moves east across New England, bringing overnight low temps into the 30s across most of the local area, even across parts of NYC on Tuesday night. Grab those jackets. Thu-Fri will bring our next chance of rain as low lvl warm air advection increases between the departing Canadian high and a low approaching across the Great Lakes. && .AVIATION /11Z SATURDAY THROUGH WEDNESDAY/... Behind a cold front, there are rain showers which are moving across city terminals as well as terminals to the north and west. These decrease late today into tonight. The winds have switched to a gusty NW flow for most terminals, except for KGON. The winds will peak generally in the 20-25 kt sustained range with gusts near 35kt at times, mainly late this afternoon into early this evening. The NW flow will lead to an improvement of category, eventually to VFR by the middle of this afternoon. Currently, conditions range from VFR to IFR. The improvement time to MVFR and VFR could be off by 2-4 hours. In terms of winds, they could occasionally be off by a few kts. .Outlook for 09Z Sunday through Wednesday... .Sunday...VFR. WNW-NW winds G25-35KT likely. .Sunday night-Tuesday night...VFR, NW winds G20-25KT possible. An isolated shower possible Sunday Night into Mon Morning. .Wednesday...VFR. && .MARINE... Westerly gales develop across all waters today as deepening low pressure lifts north along the New England coast. Gales are forecast to continue through the day Sunday. Wind gusts may briefly drop below 25 kt Sunday night before a cold front passes early Monday morning. Wind gusts of 25-30kt are likely Monday through Tuesday. Winds and seas are forecast to decrease on Wednesday as high pressure moves across the area. && .HYDROLOGY... Additional rainfall today is expected to be in the range of a quarter to half an inch with isolated higher amounts. The highest amounts will be generally over the Husdon Valley. Sunday night...scattered showers with rainfall of less than one tenth of an inch is forecast with the passage of a cold front. Thursday through Friday...A widespread rainfall of 1/2 to 1 inch is possible with the approach of low pressure from the Great Lakes. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Wind Advisory from 2 PM this afternoon to 6 AM EDT Sunday for CTZ007-008-011-012. NY...Wind Advisory from 2 PM this afternoon to 6 AM EDT Sunday for NYZ072>075-078>081-176>179. NJ...None. MARINE...Gale Warning until 6 PM EDT Sunday for ANZ330-335-338-340-345- 350-353-355. && $$ SYNOPSIS...DW NEAR TERM...JM/DW SHORT TERM...DW LONG TERM...GC AVIATION...JM MARINE...JM/DW HYDROLOGY...DW is the U.S. government's official web portal to all federal, state and local government web resources and services.