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FXUS61 KOKX 111549
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1049 AM EST Sun Feb 11 2024

.SYNOPSIS...
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Weak high pressure will build in from the west through Monday morning, then give way to deepening low pressure approaching from the southwest. A secondary low developing near the Delmarva region Tuesday morning will pass south and east of Long Island later Tuesday. High pressure will return from Wednesday into Thursday before an Alberta Clipper low passes through Thursday night into Friday. Another low may impact the region over the weekend.
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&& .NEAR TERM /THROUGH TONIGHT/...
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Near term fcst on track, adjusted to trend from current obs. While somewhat cooler today, highs will top out in the lower 50s in many spots, which is still about 10 degrees above normal. High level clouds streaming out ahead of a deepening upper trough over the Southern Plains will keep it a mostly cloudy day. Some clearing expected along with a light NW-N flow will allow for a cooler night tonight, with lows ranging from the upper 20s inland and across the Long Island Pine Barrens, to the upper 30s across the NYC metro area.
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&& .SHORT TERM /MONDAY THROUGH TUESDAY/...
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* Confidence remains medium to high across the interior for a warning level snow event (>= 6 inches) late Monday night into Tuesday. Winter Storm Watch remains up for interior portions of NE NJ, the Lower Hudson Valley, and interior southern CT. * A plowable, advisory level snow is possible for Southern Westchester, coastal CT and portions of NE NJ west of the I-95 corridor. * Uncertainty remains on the exact track of the deepening low and timing of transition to snow in the NYC metro and Long Island corridor. Weak high pressure will be across the area to start on Monday with even some sunshine before high level clouds arrive later in the afternoon. It will still be mild with highs getting up into the upper 40s. Model guidance overall has changed little the last 24h as deepening low pressure approaches from the SW late Monday, with secondary low development near the Delmarva Tuesday morning. The low then tracks to the south and east of Long Island during the day, passing near the 40N/70W benchmark. There were some slight northward trends in the ECMWF and GFS guidance, and without a damming high in place to the north, much of the area will initially start off as rain. Some of the colder guidance like the Canadian and NAM keep coastal locations largely snow, but there is lower confidence in these solutions. The easterly flow at the onset will allow for some warmer maritime air to work in across the area, especially coastal locations. The GFS has also been persistent in showing a strong mid level warm nose that even briefly pokes into some of the interior locations before going over to all snow from NW to SE the second half of Monday night. Coastal locations will be the last to turnover with NYC and Long Island likely not happening until after daybreak. The changeover looks to happen fairly quickly inland with the potential for 6 or more inches. Closer to the coast, the best chance for advisory level snows will be coastal CT and portions of NE NJ west of the I-95 corridor. For the NYC metro and Long Island, the changeover looks to be late enough to only produce minor accumulations of around an inch. An important point of emphasis with this setup is that any minor north- south adjustments in track will impact the amount of snowfall across the region. Lower amounts can be expected with a northward shift, and higher amounts at the coast with a more southern track. The precipitation will start after midnight from SW to NE, becoming heaviest in the pre-dawn hours and continuing through the morning, ending from west to east in the afternoon. Northerly winds will gust between 25 and 35 mph on Tuesday, with a few higher gusts to around 40 mph along the immediate coastline. This combined with heavy snow could limit visibilities to less than 1/2 mile. However, a limiting factor for the blowing and drifting will be that this looks to be a mainly wet snow. Temperatures across the interior will drop into the lower 30 by daybreak Tuesday, and the mid to upper 30s along the coast. So this is not a very cold airmass in place and will limit how quickly the snow starts accumulating.
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&& .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
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High pressure builds into the region behind the departing low with dry conditions through Thursday and temperatures slightly below normal to normal for the remainder of the week and into the weekend. A quick moving clipper system is expected to pass north of the region Thursday night into Friday, which could result in some rain or snow showers. Another low pressure system may impact the region over the weekend. At this time, this second low appears to have more precipitation with it than the Thursday night/Friday event, however its a bit early to get into any details on precip amounts and p- types.
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&& .AVIATION /16Z SUNDAY THROUGH THURSDAY/...
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High pressure will builds into the region today and tonight. VFR conditions expected through the TAF period. A NW flow is expected today with wind speeds 10 kt or less. There is a chance that winds may shift more to the W for mid to late afternoon, but confidence is low. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled amendments expected. OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY... Monday...VFR. Monday night...IFR or lower conditions likely. At KSWF/KHPN, rain or a snow/rain mix, changing to all snow after midnight. Elsewhere, rain possibly mixing with snow late. NE winds 10-15 G20-25 kt late, highest NYC metro/coast. Tuesday...IFR or lower cond likely. Precip changing to all snow by late morning. Snow tapering off from W-E during the afternoon, with cond possibly becoming VFR late. NE-N winds 15-20 G25-30kt, becoming NW in the afternoon. Tuesday night through Wednesday night...VFR. NW winds 10-15G20kt daytime, and 10-15G20kt at night. Thursday: Mainly VFR. W winds 10-15G20kt. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
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&& .MARINE...
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Swell of 4 ft will slowly subside today with NW winds 10 kt or less as weak high pressure builds from the west. Tranquil conditions then continue into Monday. NE winds increase Monday night ahead of an approaching deepening low pressure system from the southwest. The low then passes just south and east of the ocean waters on Tuesday. This will allow winds to reach gales on the ocean on Tuesday. Thus, a gale watch remains in effect for the ocean waters. Otherwise, SCA conditions are likely for the remaining waters with even occasional gale force gusts being possible. SCA cond are likely to continue on the ocean waters into Thursday with a tight pressure gradient over the area between the departing low and approaching high pressure. Cond eventually fall below SCA levels late Thursday through Friday, however another round of SCA cond is possible over the weekend with another low pressure system passing over or nearby the area waters.
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&& .HYDROLOGY... There are no hydrologic issues expected at this time. && .TIDES/COASTAL FLOODING...
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* Minor coastal flooding is likely across multiple high cycles through Monday night. * Widespread minor and some moderate coastal flooding are possible with the Tuesday morning/midday high tides. Water levels had touched minor thresholds in spots along NY Harbor and Jamaica Bay, a little higher than fcst. Statement may be needed for the Mon AM high tide cycle. Water levels are falling below minor thresholds this morning in S Nassau. Advy remains in effect there for the Mon AM high tide cycle. A long-running statement remains in effect for coastal Fairfield/Westchester as water levels with each high tide may touch or just barely surpass thresholds at the Stamford and/or Bridgeport gauges. Per blend of bias-corrected Stevens NYHOPS/ETSS/ESTOFS guidance, a storm passing through Mon night-Tue has potential to produce moderate flooding on the western Sound, the Long Island south shore bays of SW Suffolk/Nassau, and lower NY Harbor, and minor flooding elsewhere. Winds will be backing N around the time of high tide which could keep levels from touching moderate benchmarks on the Sound/Harbor. Have not yet issued coastal flood watches for this time frame because of that, and also to avoid confusion with ongoing earlier minor flooding.
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&& .OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Winter Storm Watch from late Monday night through Tuesday afternoon for CTZ005>008. NY...Winter Storm Watch from late Monday night through Tuesday afternoon for NYZ067>070. Coastal Flood Advisory from 8 AM to noon EST Monday for NYZ179. NJ...Winter Storm Watch from late Monday night through Tuesday afternoon for NJZ002-103. MARINE...Gale Watch from Tuesday morning through Tuesday afternoon for ANZ350-353-355.
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&& $$ SYNOPSIS...BC/BG/DW NEAR TERM...BG/DW SHORT TERM...DW LONG TERM...BC AVIATION...BC/JC MARINE...BC/BG/DW HYDROLOGY...BC/DW TIDES/COASTAL FLOODING...BC/BG