Area Forecast Discussion
Issued by NWS Upton, NY

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295 FXUS61 KOKX 152237 AFDOKX Area Forecast Discussion National Weather Service New York NY 637 PM EDT Sun Oct 15 2017 .SYNOPSIS... A cold front passes through late tonight. A broad area of high pressure will build in from the west and remain in control through the weekend. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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All obs plus stlt indicate the entire area is ovc. Cloud cover has been increased in the grids as a result. Otherwise, the fcst is on track. Upper trough and associated surface cold front approach from the Ohio Valley tonight. This will result in a gusty SW flow ahead of the front. The 12Z guidance is showing deeper-layered lift along and just behind the front tonight, as well as slightly slower progression. The lift seems to be driven by a steep frontal slope which should be sufficient for showers. The best chance for showers due to lift and available moisture is now appearing to be from NYC metro and east. Rainfall amounts still though look to be less than a tenth of an inch, but perhaps some isolated higher amounts up to a quarter inch are possible. Still looking at another mild night as the cold advection occurs late. Lows will be about 10 degrees above normal with readings in the in the mid to upper 60s.
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&& .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... Cold front pushes east of the area by daybreak with strong cold advection and gusty NW winds. Temperatures will return to near seasonable levels in the upper 50s to lowers 60s, but likely will feel cooler with the strong NW flow. Skies will gradually clear from morning into early afternoon. Unseasonably cold conditions Monday night with temperatures in the 30s in the suburbs,to the lower 40s NYC metro. Its possible that a frost advisory may be needed for the interior. However, there could be enough wind and dry air to limit frost to patchy coverage. && .LONG TERM /TUESDAY THROUGH SUNDAY/... Mainly a temp fcst in the long term as an approximately 590 dam h5 ridge builds along the ern seaboard. The superblend was used for the fcst, except for Tue ngt where the mex guidance appears to be picking up on a climatologically decoupled setup. Because of this, temps were adjusted blw the superblend. If the winds indeed go calm, temps about 5 degrees lower than fcst will be possible. Otherwise, temps will quickly rebound to abv normal Wed and remain thru the weekend. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... A cold front will approach late this afternoon and this evening, then crosses the region tonight. Conditions are starting to improve across the area terminals. Many spots now MVFR. Less confidence of VFR conditions occurring this afternoon around 20-22z. Have amended TAFs to reflect this, however still can not rule out a period of VFR conditions late this afternoon into the evening. Any location that goes VFR, should not last long, as MVFR conditions come back into the area after sunset. Cold front approaches this evening, crossing tonight. Showers are expected to develop along the front, along with some MVFR conditions. There is a chance some IFR conditions re-develop overnight. Confidence of occurrence too low to include in the TAF. S to SW winds increase to 10 to 15 KT with gusts 20-25kt this afternoon, continuing for the evening push. Winds shift to NW after 07-10Z with gusts 20-25KT. Gusts may be occasional this evening. .OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY... .Monday...Low chance for early AM showers and MVFR, otherwise VFR. NW winds G20-25KT. .Tuesday-Friday...VFR. && .MARINE... SCA winds and seas expected to build on the ocean in a strengthening SW flow ahead of an approaching cold front this aft/eve, and with the NW flow in its wake late tonight into early Mon morning. Marginal SCA gusts are expected on nearshore waters, pre and post frontal during this time as well. Marginal SCA gusts may continue on the nearshore waters through the day Monday, nonetheless SCA seas are expected to continue on the ocean. Higher confidence in a period of SCA winds re- developing across all waters Mon eve/night in wake of secondary cold front. Winds and seas will fall blw sca lvls Tue mrng, and remain blw criteria thru the weekend. && .HYDROLOGY... No hydrologic issues expected through the end of next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory until 6 PM EDT Monday for ANZ330-335-338- 340-345. Small Craft Advisory until 6 AM EDT Tuesday for ANZ350-353-355. && $$ SYNOPSIS...JMC/DW NEAR TERM...JMC/DW SHORT TERM...DW LONG TERM...JMC AVIATION...BC MARINE...JMC/DW HYDROLOGY...JMC/DW is the U.S. government's official web portal to all federal, state and local government web resources and services.