Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 140555 AFDOKX Area Forecast Discussion National Weather Service New York NY 155 AM EDT Sat Oct 14 2017 .SYNOPSIS... A surface trough shifts into the area tonight and remains nearby through Saturday night. Abnormally mild and summer-like on Sunday ahead of a cold front that will cross the region Sunday night. High pressure then dominates for the work week with dry weather and near seasonable temperatures, though with gradual warming by late in the week. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... Patchy drizzle and light rain is starting to develop across the area in weak, low-level warm advection as a subtle short wave passes to the north. A surface trough shifts into the area tonight. Moisture convergence along this boundary along with lower level omega and isentropic lift will bring increasing chances of light rain mainly after midnight. Models have been trending deeper with this moisture and stronger with the lift, so decided to not mention drizzle in the forecast. Best overall rain chances will be in the vicinity of the city and NE NJ. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/... The trough shifts east Saturday and Saturday night. Moisture convergence and lift move with it. Best overall chances of rain during the day will be in the morning and over LI and CT. Guidance blend for high temps, which is cooler than the previous forecast, looked good considering the anticipated cloud cover. Lower chances of rain during Saturday night, with the intensity becoming more likely to be light or even possibly drizzle late at night. Areas of fog probably develop overnight as well. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... The NWP suite of models including the 12Z GEFS are in reasonable agreement through next week. There have been only minor changes in the forecast since early this morning with the light potential precipitation event Sunday night associated with a cold FROPA. Otherwise, dry/fair weather prevails through the work week. Details: Southwest flow ahead of the cold front is fairly strong with gusts likely into the mid to upper 20`s (mph) range on Sunday with highest gusts across the coast. Winds shift to Northwest overnight with the passage of the cold front. Have raised POPs to likely with support of the GFS and EC 12Z deterministic runs as well as surrounding NWS WFOs for the overnight. NAM and SREF suggest a lower POP, but regardless - fully expect less than 1/4". Winds are gusty again on Monday from the northwest with cold advection. Otherwise, temps on Tuesday only top out near 60 - about 5 degrees below normal, but then recover to around 70 by Thursday with tranquil conditions. Warmer yet for Friday. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
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High pressure nosing in from the Canadian Maritimes will continue to retreat today, while a weak wave of low pressure off the North Carolina coast moves slowly north towards Long Island this morning and then northeast this afternoon. MVFR and then IFR conds in drizzle and rain are expected to develop into the region for the morning push. The rain and drizzle will taper from W to E later this morning into early afternoon, with conditions improving to MVFR. A period of VFR conditions likely for NYC/NJ terminals late this afternoon, while northern and eastern terminals could hold onto mvfr cigs all day. IFR conditions in stratus fog likely once again tonight. Light ne winds this morning, possibly giving way to light s/se sea breezes along the coastal terminals this afternoon. .OUTLOOK FOR 06Z SUNDAY THROUGH WEDNESDAY... .Late Tonight...IFR conditions with low ceilings and fog. .Sunday...Improving to VFR in the morning, then chance of showers at night with MVFR conditions. SW winds G25KT. .Monday...Chc early AM showers, otherwise VFR. NW winds G20KT. .Tuesday and Wednesday...VFR.
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&& .MARINE... Have converted the general SCA on the ocean waters to a SCA for hazardous seas. Also have extended it through Saturday afternoon with collaboration from the surrounding offices. The SCA might need to be extended into at least a portion of Saturday night, but confidence in occurrence and duration is not high enough at this time. All other waters will have sub-advisory conditions prevailing through Saturday night. SCA conditions appear likely Sunday into Monday on the Ocean Waters ahead and in the wake of a cold front. A brief period of SCA gusts are possible on the Sound and Bays as well as pre and post frontal overnight Sunday into early Monday. Tranquil conditions are expected from Tuesday into the end of the week. && .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 for hazardous seas until 6 PM EDT this evening for ANZ350-353-355. && $$ SYNOPSIS...JC/Tongue NEAR TERM...JMC/JC/MD SHORT TERM...JC LONG TERM...Tongue AVIATION...NV MARINE...JC/Tongue HYDROLOGY...JC/Tongue

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