Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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444 FXUS61 KOKX 052147 AFDOKX Area Forecast Discussion National Weather Service New York NY 447 PM EST Fri Dec 5 2025 .SYNOPSIS... A weak low pressure trough extending north from low pressure moving off the southern Mid Atlantic coast will impact the area mainly late tonight into Saturday morning. Weak high pressure will then be over the area Saturday night into Sunday. A strong cold front will move through Sunday night. High pressure builds from the west Monday, remaining in control through Tuesday. A couple of low pressure systems pass to the north and may impact the area from the middle to late next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Main update was to add a slight chance for flurries across the eastern 2/3 of the forecast area for the next few hours as there are some light returns seen on radar as well as some observers noting flurries moving through. High pressure shifts offshore this evening with light return flow developing. As a weak low pressure system passes well to the south and another shortwave passes well to the north, an inverted trough the connected these two systems develops over the area tonight. Given the weak southerly flow and increase in low level moisture, this may result in very light precipitation this evening through early Saturday morning. The most difficult aspect to this forecast is the p-type if this light precipitation develops. Given the previously cold air still over the area, the surface will likely be below freezing for much if not all of the area initially. The limited vertical extent of the moisture profile brings into question if enough ice nuclei will exist to result in snow, otherwise a freezing drizzle is more likely. The thought process now is that the influence of coastal convergence may enhance lift just enough to produce enough ice nuclei resulting in flurries or a light snow. This may not encompass the entire area and it`s very possible that while some areas see light snow or flurries, other areas may see more of a freezing drizzle or plain drizzle depending on the surface temperature. Surface temperatures along the immediate south coast, mainly Long Island and southern NYC may slightly warm enough overnight to switch any frozen precip to freezing drizzle to plain drizzle by morning, but this remains uncertain. For any areas where light snow becomes more dominant, a dusting or a light coating of snow is possible on cooler/grassy surfaces. If freezing drizzle develops, anything below freezing will be subject to a glaze of ice, including any untreated roadways. An SPS is issued for mainly coastal areas to reflect the possibility of hazardous conditions developing overnight due to any freezing drizzle. If a more persistent area of freezing drizzle develops, a short-fused Winter Weather Advisory may be issued. Low temperatures expected to be in the 20s much of the area, though the immediate coast may remain in the low 30s. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... Weak high pressure builds in from the west Saturday afternoon through Sunday morning resulting in generally dry conditions. Temps after precip ends on Sat will rise to the upper 30s/lower 40s, then fall back once again to the 20s and lower 30s. With no change in air mass for Sunday high temps should once again reach the upper 30s/lower 40s in most spots. Cold fropa Sunday night will be preceded by a chance of snow showers mainly inland and out east. Fropa should take place after midnight, with colder air starting to coming in on a gusty NW flow, and lows from the upper teens well inland to the 20s elsewhere. && .LONG TERM /MONDAY THROUGH FRIDAY/... * Some of the coldest air of the season so far moves in early next week. High temperatures Monday and Tuesday likely in the upper 20 and 30s region-wide, with morning wind chills in the single digits and teens. Arctic high pressure builds in from the west Monday, with the center moving overhead Monday night into Tuesday morning. This will usher some of the coldest air thus far this winter season. 850 mb temperatures in the -12 to -18 C range across the forecast area Monday will translate to highs in the upper 20s to lower 30s, with much of the forecast area not climbing above the freezing point (32 degrees). Low temperatures Monday night into Tuesday morning could potentially be a few degrees colder depending on how clear the skies are and how calm the winds are for optimal radiational cooling. Right now, stuck with the NBM, which is giving lows in the single digits across northern portions of the Lower Hudson Valley, teens for most other places, and 20s in NYC. The high pushes off the Northeast Coast Tuesday, allowing a warm front to approach from the southwest and low pressure to move across the Great Lakes and pass north of the area Tuesday night into Wednesday morning. Therefore, dry conditions are in store from Monday through Tuesday, with just a slight chance of precipitation for portions of the forecast area Tuesday night. The warm front may lift north during the day Wednesday as another fast moving low pressure system approaches from the west, farther south than the previous one. This too is expected to pass north, rounding the base of the upper trough that is in place Wednesday night. This may give the region a better chance for precipitation Wednesday into Thursday, but it looks to be light. The associated cold front looks to push through Wednesday night, allowing high pressure to build in for Thursday. Another quick moving system approaches from the west late in the week, but there is a great deal of uncertainty among the models as to the track and strength of the low. Warmer, but still well below normal temperatures expected for Wednesday, with highs in the upper 20s to around 40 across the area (warmer for coastal areas). Near normal temperatures on Wednesday with the warm frontal passage, but then slightly cooler for Thursday with the cold frontal passage. && .AVIATION /21Z FRIDAY THROUGH WEDNESDAY/... A surface trough shifts through the terminals late tonight, followed by weak high pressure for Saturday. Mainly MVFR for the rest of today into tonight. A stray flurry or light snow shower possible before a better chance of light snow occurs towards midnight tonight, and remaining possible through part of the morning push. Brief IFR still possible late tonight through the morning push. Improvement to VFR late Sat morning/early aftn. Light easterly component winds today followed by light and variable winds tonight. WSW winds below 10kt for Saturday aftn. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Brief flurries/light snow possible this afternoon and evening before chances increase toward midnight tonight. Still a low chance of -FZRA or -FZDZ, but confidence is not high enough to include in the TAF at this time. .OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY... Saturday: VFR. Sunday: Mainly VFR. Chance of MVFR and light rain/snow mix at night. Monday and Tuesday: VFR. NW-N gusts 20-25kt Monday morning. Wednesday: Chance of MVFR and rain showers. S-SW gusts 20-25kt possible. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Sub-SCA conditions through the weekend. SCA conditions are possible through much of next week beginning Monday as multiple low pressure systems could impact the area. && .HYDROLOGY... No hydrologic impacts are expected at this time. && .TIDES/COASTAL FLOODING... Water levels are running high around the times of high tide due to yesterday`s full moon, with departures of 1 ft or less needed to reach minor flood thresholds today and Saturday. Latest combo of bias-corrected ETSS, STOFS, and NYHOPS ensemble 50th percentile guidance has trended upward slightly, and indicates that water levels may get close to minor flood thresholds with the high tide late this morning in isolated spots along the SW CT coastline. Due to the isolated nature have not issued a statement. Water levels may touch minor flood thresholds with the Saturday morning late morning/midday high tide cycle in spots along the back bays of Nassau and Queens, tidal waterways of NE NJ, the SW CT coastline, and at Shinnecock and Montauk out east. A coastal flood statement may eventually be issued to address this. && .CLIMATE... High temps today may also be close to daily record low maxes at KEWR/KLGA/KJFK. Record Low Maximum Temperatures: KEWR: 31/2002 KBDR: 28/2002 KNYC: 22/1886 KLGA: 32/2002 KJFK: 33/2007 KISP: 30/2002 && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JP/MW NEAR TERM...JP/MW SHORT TERM...MW LONG TERM...JP AVIATION...JC MARINE...JP/MW HYDROLOGY...JP/MW TIDES/COASTAL FLOODING... CLIMATE...