Area Forecast Discussion
Issued by NWS Upton, NY

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015 FXUS61 KOKX 231330 AFDOKX Area Forecast Discussion National Weather Service New York NY 830 AM EST Thu Feb 23 2017 .SYNOPSIS... High pressure will remain steady over the western Atlantic through Friday. A frontal system approaches Saturday and crosses the region Saturday Night. High pressure builds over the area during the early part of next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Stratus/fog advecting up from central NY will likely briefly overspread the NYC/NJ metro and surroundings early this morning before lifting mid to late morning. Otherwise...Early spring like pattern...with unseasonably mild and moist airmass advecting up the coast under East Coast ridging. Dense fog across most coastal areas should gradually mix out through the morning...but could linger into the afternoon across immediate south coastal areas. Stratus developing this morning across much of the region will likely hold tough into the afternoon...possibly all day along coastal areas. Temps will run well above least 50s coast and 60s interior. If breaks of sun develop this afternoon...temps could run around 70 degrees across NE NJ/NYC metro/Lower Hud valley in SW flow. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... PAC shortwave and associated low pressure system move east through Southern Quebec tonight with trailing cold front pushing towards the region late. Models have backed off on how far south the cold front will press tonight...stalling over or just north of the region late tonight/Friday morning. The front...with weak shortwave energy moving through aloft...will likely act as a focus for some light rain showers/drizzle...with fog development in the moisture pooling to the south. Fog could once again be dense. Friday will likely feature conditions similar to today...with forecast uncertainty in location of the stalled front and how quickly it moves back north. If front lingers in the area...drizzle and fog would linger all day. If front stays north or moves to the north...a gradual lifting of fog and potential for afternoon breaks in stratus across interior would be favored. Coastal areas though have likelihood to remain in marine layer in either scenario. Temps will be once again be well above normal in the 50s coast/60s interior...but once again if breaks of sun can develop across the interior temps would make a run to 70. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... A cold front will move across the area on Saturday before pushing offshore Saturday night. As the moisture increases across the area during the day on Saturday expect showers to develop. An isolated thunderstorm is also possible, mainly during the afternoon and evening. High temperatures on Saturday will be in the upper 50s to lower 60s. High pressure will build into the area Saturday night through Sunday night. Temperatures Saturday night will be in the mid to upper 30s with temperatures on Sunday in the mid to upper 40s. High pressure moves offshore Monday, as a storm moves towards the area. A chance of rain and snow showers are possible with the storm passage. The storm will move offshore Monday night. Several shortwaves will interact with a frontal boundary near the area resulting in chances of light precipitation through the middle of the week. Temperatures during this time period will be generally around 5 to 10 degrees above normal. && .AVIATION /12Z THURSDAY THROUGH MONDAY/...
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High pressure will slowly drift eastward off the Mid Atlantic coast during the day. A cold front will approach from the north overnight tonight into Friday morning, pushing north as a warm front later Friday. LIFR conditions continue this morning across most of Long Island and southern Connecticut. Elsewhere, fog and low stratus have developed northward across most of the city terminals. KLGA and KTEB will continue to be along the northern edge of the stratus and therefore should experience slightly better conditions than the other city terminals. Conditions will slowly improve starting around 15Z this morning, although MVFR conditions will linger into the early afternoon. Most terminals then become VFR for a period this afternoon with the exception of the coastal and eastern terminals, which will remain MVFR through the afternoon. There remains quite a bit of uncertainty as to how quickly conditions improve across the area late this morning and into the afternoon. MVFR and IFR conditions return tonight as fog and low stratus redevelop across the region. In addition, areas of drizzle or light rain showers are possible overnight. Light and variable to calm winds at all terminals this morning will become S-SW at less than 10 kt during the day. Winds then become light and variable again outside of the city tonight. NY Metro Enhanced Aviation Weather Support... Detailed information, including hourly TAF wind component forecasts, can be found at: http:/ KJFK TAF Comments: Timing of improvement to MVFR late this morning into the early afternoon may be off by 1-2 hours. KLGA TAF Comments: Timing of deterioration to IFR this morning and subsequent improvement late this morning into the early afternoon may be off by 1-2 hours. KEWR TAF Comments: Periods of LIFR visibilities possible this morning. Timing of improvement to MVFR late this morning into the early afternoon may be off by 1-2 hours. The afternoon KEWR haze potential forecast is YELLOW...which implies slant range visibility 4-6SM outside of cloud. KTEB TAF Comments: Timing of deterioration to IFR this morning and subsequent improvement late this morning into the early afternoon may be off by 1-2 hours. KHPN TAF Comments: Timing of deterioration to IFR this morning and subsequent improvement late this morning into the early afternoon may be off by 1-2 hours. KISP TAF Comments: Timing of improvement to MVFR late this morning into the early afternoon may be off by 1-2 hours. .OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY... .Friday-Saturday...MVFR to IFR in stratus and fog with periods of light rain and drizzle Friday morning. Conditions could improve to VFR for a period during the day on Friday before lowering again Friday night. .Saturday night...MVFR likely with rain. .Sunday...VFR. .Monday...VFR early...becoming MVFR. Chance of rain or snow.
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&& .MARINE... Main hazard through Friday Night for nearshore waters will likely be dense fog as an unseasonable mild and moist airmass overspreads the cool waters. Otherwise, high pressure over the western Atlantic brings a persistent s/sw flow but sub sca conds to the local waters through Friday. Southerly wind gusts on the ocean could run to close to 20 kt this eve. An easterly swell and southerly wind waves may bring ocean seas close to 5 ft tonight into Friday. Winds and waves will remain below Small Craft Advisory levels Friday night. Small Craft Advisory levels likely Saturday night as a cold front moves across the area waters. Small Craft Advisory conditions are then likely on Sunday, and possible on Monday. Winds and seas improve on Tuesday. && .HYDROLOGY... No hydrologic impacts are expected through next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Dense Fog Advisory until 10 AM EST this morning for CTZ010>012. NY...Dense Fog Advisory until 10 AM EST this morning for NYZ078>081- 179. NJ...None. MARINE...Dense Fog Advisory until 1 PM EST this afternoon for ANZ330- 335-338-340-345-350-353-355. && $$ SYNOPSIS...Fig/NV NEAR TERM...NV SHORT TERM...NV LONG TERM...Fig AVIATION...FEB/CB MARINE...Fig/NV HYDROLOGY...Fig/NV is the U.S. government's official web portal to all federal, state and local government web resources and services.