Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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925 FXUS61 KOKX 202043 AFDOKX Area Forecast Discussion National Weather Service New York NY 343 PM EST Thu Nov 20 2025 .SYNOPSIS... High pressure remains directly over the region tonight. The high then moves offshore on Friday with a frontal wave moving across Friday night into Saturday morning. High pressure then builds back Saturday afternoon and Saturday night and will remain in control through early next week. The high moves offshore on Tuesday followed by the next frontal system impacting the area late Tuesday into Wednesday. High pressure should build towards the area next Thursday. && .NEAR TERM /THROUGH FRIDAY/... High pressure will be in place and directly over the region tonight. This will provide ideal radiational cooling conditions through the evening and basically for the first half of the night. After that more upper level moisture and upper clouds arrive from the W and SW. Therefore look for temperatures once again to drop through the early to late evening across the entire area. After that there will be a floor put in place on temperatures from west to east later in the overnight. With temperatures radiating quickly and the air mass not overly dry look for frost to form in the non-metro areas once again tonight. After midnight, and especially after 07-08z more upper and mid level cloud cover moves in. Minimum temperatures will range from the upper 30s to around 40 in much of the metro, to mainly upper 20s and 30s elsewhere. Look for more in the way of clouds on Friday as surface high pressure slips offshore. A return flow out of the SW gets established during the early afternoon as dew point readings begin to inch up into the 40s. This advection of a milder air mass will get temperatures back to seasonable levels despite clouds, mainly into the lower half of the 50s for daytime maximum temperatures. && .SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... During Friday evening clouds lower with the NWP guidance now not as bullish on rain probabilities. Consensus NWP PoPs have continued to come down some. Now introduce chance PoPS in the 0-3z timeframe, with low end likely PoPs applied to roughly the southern third of the forecast area towards and after 06z. The reason for guidance backing off is the suppression of moisture as it streaks ENE out of the Tennessee Valley during Friday night. This suppression is being caused by a slightly further south presence of an upper level low into SE Canada and thus a further south placement of a strong upper level confluence zone into Northern New England. This serves to dampen the more southern shortwave making low pressure weaker and more elongated. This results more in a wavy frontal system per se which will have difficulty spinning up much in the way of warm air advection to drive meaningful precipitation. Thus chance to low end likely PoPs are utilized into early Saturday morning. Rainfall amounts will be rather light with only a few hundredths to mainly just under a quarter inch of liquid expected. During the day Saturday the frontal system begins to eject east with rain getting east early on. The timing of clearing just behind the the frontal passage appears to be 12-13z NW to 16-18z SE. Thus after a cloudy start, look for clearing to work in from WNW to ESE through the morning and early afternoon. There will be a noticeable air mass change behind the front by later in the day Saturday and Saturday night, but nothing unusual for this time of year. Max temperatures during the day Saturday will be a couple of degrees cooler overall with upper 40s to lower 50s. It does turn seasonably cold Saturday night with temperatures getting below freezing in all outlying areas, with 20s across the interior, near 30 along the coast, with middle 30s into the metro under mainly clear skies. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Key Points: * Rain is forecast late Tuesday into Tuesday night. The chance of rain continues on Wednesday, but confidence is much lower with the extent and duration of any rain. * Seasonably cool and dry conditions Sunday and Monday become milder Tuesday and Wednesday. * The potential remains for a seasonably cool and dry Thanksgiving. Mean upper troughing will push off the east coast on Sunday allowing ridging to return Monday into Tuesday. The ridge axis should slide to our east Tuesday night ahead of the next frontal system, which moves across the area through Wednesday. The guidance is in good agreement with warm advection rain Tuesday night as the associated warm front lifts towards the region. The overall pattern supports a steady rain with the likelihood of no hydrologic impacts. Uncertainty increases for next Wednesday as there are significant differences in the amplitude of the associated upper trough and any trailing wave. The parent low pressure will lift well to our north and west, putting the region in a milder regime. The main questions revolve around whether a wave develops along the trailing cold front. If a wave develops along the cold front, another round of rain/showers could occur. Otherwise, the cold front may move through mostly dry as the main forcing appears to pass well to our NW. These details may take a few more days to resolve in the modeling, but the NBM chance PoPs look reasonable for now. Guidance is then in good agreement with the cold front pushing offshore Wednesday night/early Thursday, which should lead to improving conditions for the Thanksgiving holiday. && .AVIATION /20Z THURSDAY THROUGH TUESDAY/... High pressure moves offshore late tonight into Friday. A cold front approaches Friday afternoon. VFR through the TAF period, though there is a low chance of MVFR cigs moving in mid to late Friday morning, mainly for NYC terminals and points north and west. Winds generally light and variable through the forecast then becoming a light S flow, or light and variable, with a shift more toward the SW Friday morning. Wind speeds will still be less than 10 kt however. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled amendments expected. .OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY... Friday afternoon: Mostly VFR. MVFR possible late in the afternoon. SW winds 10 kt or less. Friday night through Saturday: MVFR or lower at times in rain. Becoming VFR Saturday afternoon into the evening. SW winds 10 kt or less Friday night becoming NW to N Saturday 5 to 10 kt. Sunday through Monday: VFR. Tuesday: VFR possibly becoming MVFR in the afternoon. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Tranquil conditions will be in place across the coastal waters tonight before winds and seas increase some into Friday and Friday evening, but conditions will remain below small craft through Friday night. Behind the front look for the winds to be out of the N and NW with primarily sub advisory conditions prevailing, although there may be a period of marginal small craft conditions on the ocean during the day Saturday and into a portion of Saturday evening. Afterwards high pressure builds Saturday night resulting in conditions remaining below SCA levels Sunday through Tuesday. && .HYDROLOGY... There are no hydrologic impacts expected through the middle of next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JE/DS NEAR TERM...JE SHORT TERM...JE LONG TERM...DS AVIATION...JP MARINE...JE/DS HYDROLOGY...JE/DS