Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 210821 AFDOKX Area Forecast Discussion National Weather Service New York NY 421 AM EDT Fri Oct 21 2016 .SYNOPSIS... Showers today as a cold front gradually approaches from the west and then moves through late tonight. Deepening low pressure will track across New England into Quebec this weekend bringing windy conditions to the Tri-State. A cold front will pass through on Monday, followed by building high pressure through the middle of the week. && .NEAR TERM /THROUGH TONIGHT/... Dense Fog remains spotty, so we will continue with a statement for Suffolk County on Long Island and in the elevated areas of SE CT, the Hudson Valley and into NE NJ. Also along the CT River. Would say that the warm front extends from the CT Coast to near Newburgh as of 08Z. While latest RADAR shows very little PCPN in the local area, NWP has been persistent in showers, some heavy developing this morning from the Jersey Coast north across the City and into New England. The PCPN Shifts to the East this afternoon. Thus, would expect a period of dry WX for the Mid Day into mid to late AFTN (lowered POPs to 30%) for all but eastern sections (Likely POPs there). Have removed thunder from the forecast as instability is very marginal - but would not be surprised is there were a flash or two with the shower activity this morning that pushes east this afternoon. By evening....PCPN comes back from the west as the cold front finally gets here. With this in mind, have followed the GFS MOS for temps into the lower to mid 70s - that may even be a bit low. Also, with the Cold Advection not starting until very late tonight, have gone with the warmer GFS MOS again tonight. && .SHORT TERM /SATURDAY/... Winds, cool temps, clouds and light showers make for a real fall like day on Saturday. CAA keeps temps steady of falling slightly thought the day. Showers are scattered and light...mainly in the morning. Skies become partly sunny as we downslope of the Appalachians in the AFTN. POPs go from 50 down to 30 through the day. Main story is the wind which will gust to 40 mph in the afternoon (just below advisory level of 45+. Some airports like JFK is have sustain wind speeds into the lower 30s - which is technically advisory criteria). && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Global models remain very similar with the evolution of the system this weekend as a cutoff low embedded in a negatively tilted upper trough lifts northward across New England and into eastern Canada. Showers tapper off from south to north Saturday night as moisture and forcing lift northward with the low. Gusty west winds up to 35 mph will continue through much of Sunday with around a 980 mb low across eastern Canada. A clipper type system will be racing towards the forecast area Sunday night into Monday morning. This will allow winds to back briefly to the west-southwest. The cold frontal passage looks to be early enough in the day to not allow much of a warmup, so high temperatures are similar to Sunday, which is close to or slightly below seasonable. The airmass that builds in for the Tuesday and Wednesday time period looks to be around 10 degrees below average, and will have the potential to produce a freeze across much if not all of the interior, possibly getting into some of the coastal zones. A frontal system of Pacific origin approaches from the Great Lakes on Thursday. There are magnitude issues with how deep the low is between the 00Z GFS and ECMWF, but overall the timing with this system is remarkably close for this far out in time. && .AVIATION /08Z FRIDAY THROUGH TUESDAY/... A warm front lifts to the north early this morning, followed by a cold front approaching from the west and a wave of low pressure approaching from the south today. SE/ESE winds of 5 to 10 kt through the day...becoming light and variable this evening. Early Morning: Conditions improving to mvfr...except local ifr interior wake of warm frontal passage between 06z and 08z. Then indications that conditions come back down to widespread ifr/lifr towards daybreak...but some uncertainty on timing. Late Morning/Afternoon: Improvement to mvfr vsby with ifr cigs as the morning progresses...continuing thru the afternoon. SHRA likely. Low prob of an isolated tsra. Evening: Potential deterioration to widespread LIFR or lower conditions this evening. SHRA likely. .Outlook for 06Z Saturday through Tuesday... .Late Tonight...Improvement to MVFR conditions in wake of cold frontal passage...with continued shower activity likely. NW winds G30-35KT developing. .Saturday...Becoming VFR. WNW-NW winds G25-30KT likely. .Saturday Night...Most likely VFR with very low chance of MVFR. WNW-W winds G30-35KT likely. .Sunday...VFR. W winds G25-30KT likely. .Sunday Night-Monday Night...VFR with isolated to scattered showers possible. WNW-NW winds g20-25 kt possible at eastern terminals Sunday night. NW winds g20-25KT possible Monday/Monday Night. .Tuesday...VFR with NW winds g20-25KT possible. && .MARINE... Fairly tranquil today. Seas increase on the Ocean tonight. Main even is prolonged Gales this weekend as low pressure deepens to our north. Gales are likely to continue across the waters on Sunday, especially across the ocean waters. Wind gusts may briefly drop below 25 kt Sunday night before a cold frontal passage on Monday brings a return to SCA levels through Tuesday. && .HYDROLOGY... Showers today and tonight. Totals should average 1/4 - 1/2". No hydrologic problems are expected. Light PCPN is expect on Saturday. Mainly dry weather is expected thereafter. && .TIDES/COASTAL FLOODING... More isolated minor coastal flooding with this afternoon`s high tide cycles. Generally 1-2 ft departures are needed for minor flooding. A statement will be issued. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Gale Warning from 6 AM Saturday to 6 PM EDT Sunday for ANZ330- 335-338-340-345-350-353-355. Small Craft Advisory for hazardous seas from 6 PM this evening to 6 AM EDT Saturday for ANZ350-353-355. && $$ SYNOPSIS...Tongue NEAR TERM...Tongue SHORT TERM...Tongue LONG TERM...DW AVIATION...NV MARINE...Tongue/DW HYDROLOGY...Tongue/DW TIDES/COASTAL FLOODING... is the U.S. government's official web portal to all federal, state and local government web resources and services.