Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KOKX 180223 AFDOKX Area Forecast Discussion National Weather Service New York NY 923 PM EST Tue Jan 17 2017 .SYNOPSIS... Weak low pressure and a warm front pass nearby tonight into Wednesday morning with high pressure slowly building in behind it into Friday. This is followed by a weak wave of low pressure passing to the south Friday night. High pressure then returns this weekend before the next low pressure and associated frontal system impacts the area early next week. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
-- Changed Discussion --
The forecast remains on track this evening. Rain continues tonight as a triple-point low and warm front approach. Models have the low passing just south of Long Island. The warm front may briefly lift through some of the southern sections tonight, but even north of the front, expecting surface temperatures to be above freezing. There is however some uncertainty with the amount of cooling aloft over much of the CT zones early this evening in response to better lift and relatively drier low level air. Will go with a chance of sleet mixed in with the rain for these areas during this period. Moisture above around 800mb dries out somewhat after midnight, so lighter rain or drizzle is expected. Fog is expected for the overnight hours, and although MAV and NAM MOS guidance doesn`t hint at it, there could be a chance of dense fog formation as the low center moves just south of Long Island, causing very light to calm winds for at least a few hours. At least the time-lagged NARRE has been showing an upward trend for the chance of dense fog as the night progresses.
-- End Changed Discussion --
&& .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... High pressure slowly builds in behind the departing low during Wednesday and Wednesday night. Models in good agreement regarding a good amount of low level moisture lingering during the day. Fog probably lingers into part of the morning, and with a few weak shortwaves passing through, cannot rule out some light rain or drizzle. High temperatures will be above normal. Remaining cloudy Wednesday night, and outside of a low chance of light rain or drizzle over eastern LI and SE CT, it should be dry with above-normal temperatures. && .LONG TERM /THURSDAY THROUGH TUESDAY/... High pressure builds across the area through Friday. A weak wave of low pressure will move into the upper Great Lakes Friday and its associated warm front will approach the area Friday night into Saturday. Expect a period of showers with the passage of this front but overall rainfall amounts will be light. High temperatures Thursday and Friday will be in the middle and upper 40s for most locations and near 50 degrees in the NYC and NE NJ metro. High pressure builds down from southeast Canada for the weekend with high temperature in the low to mid 40s and lows in the lows to mid 30s. A stronger system will move slowly across the Ohio Valley region Sunday with its associated frontal system gradually approaching the area early next week. As the system moves across the central states it will pull moisture from the Gulf of Mexico, resulting in a possible significant rainfall event. Confidence in specific details is low at this time. High temperatures for the beginning of the week through Tuesday will be in the mid to upper 40s. Low temperatures will be in the upper 30s to lower 40s. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
Low pressure develops off the Mid-Atlantic coast this evening, then tracks to the south of Long Island overnight and to the southeast of Long Island Wednesday. Conditions becoming IFR throughout this evening, with periods of LIFR KLGA/KHPN/KGON/KSWF/KISP and isolated LIFR elsewhere through early Wednesday morning. Conditions slowly improve Wednesday to MVFR from W to E. Winds veer from E to NE to N-NW through Wednesday. Speeds generally under 10KT, except speeds around 10KT at city/coastal terminals. .OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY... .Wednesday night...Becoming VFR. .Thursday-Friday...VFR. .Friday night...Chance of MVFR or lower. .Saturday-Saturday night...VFR. .Sunday...Chance of MVFR of lower, with best chance at CT/Long Island Terminals.
-- End Changed Discussion --
&& .MARINE... Sub-SCA conditions continue on the waters tonight as a weak low center shifts through the local ocean zones overnight. With very light winds for a few hours and plenty of low level moisture, might need to go with a dense fog advisory at some point for tonight into tomorrow morning. Not enough confidence to issue one at this time. The low center shifts farther offshore through the day Wednesday, but strengthens as it does. Gusts to 25 KT with 5 FT seas are expected over the ocean waters east of Moriches Inlet starting in the afternoon. Will go with a SCA only through the afternoon for now, and let subsequent shifts expand it in time and area as needed as there is a chance that a swell brings seas to 5 FT to the other ocean zones starting Wednesday night. Winds and seas on all waters are forecast to be below SCA levels Thursday into the weekend. && .HYDROLOGY... No hydrologic impacts are anticipated with the additional rainfall occurring through Wednesday morning. Potential exists for a significant precipitation event early next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory from noon to 5 PM EST Wednesday for ANZ350. && $$ SYNOPSIS...JC/Fig NEAR TERM...JMC/JC SHORT TERM...JC LONG TERM...Fig AVIATION...Maloit MARINE...JC/Fig HYDROLOGY...JC/Fig is the U.S. government's official web portal to all federal, state and local government web resources and services.