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FXUS61 KOKX 032052
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
352 PM EST Wed Jan 3 2024

.SYNOPSIS...
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Two weak frontal systems, one passing to the north, and the other passing to the south, will affect the region late tonight into Thursday. High pressure starts to build in to the west Thursday night and remains in control into Friday night. Low pressure will pass south and east of the region late Saturday into Sunday, bringing rain and snow to the region. A deep low may pass west of the area by the middle of next week, producing stormy conditions across the Tri-State Region.
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&& .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
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Phasing northern and southern stream systems will affect the region by late tonight as a full latitude upper trough moves toward the east coast. Both surface systems will be rather weak moving into the area late tonight, with the southern system moving close to the area by 11Z Thursday. So, will have an area of slight chance probabilities to the north, and then another area of slight chance to the south, with the better chances remaining off shore. Cold air will be in place for snow showers across the land and rain/snow showers off shore.
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&& .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY/...
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The upper trough will remain progressive during Thursday, moving off shore 21Z Thursday to 00Z Friday. Again, will keep just slight chances for precipitation across the southern land areas. With day time insolation snow showers may mix with or briefly go over to rain showers before ending late in the day. A weak cold front will the northern passes to the east by early Thursday evening. The southern stream system begins to deepen well to the south and east late Thursday through Thursday night as a strong 1030/1031 high builds into the area from the west. A period of gusty northwest winds becomes likely late Thursday into Thursday night, and then diminish as the surface high builds toward the region.
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&& .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
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No major changes with the 12Z model cycle with the general idea of the low for this weekend. There remain some differences wrt the exact track however. The ECMWF is the furthest N, and looks like an outlier when compared to the GFS and GEM, which are further S. The GFS Ensemble mean is even further S, so the fcst has been tweaked towards a more sly, colder soln. The models are often too warm with sfc temps this far out, particularly on the cold side of the sys. Couple this with a spread in tracks, and the NBM looks too warm attm. The end result could be warmer if the track ends up farther N, but based on the GFS ensemble and the low not getting to 40N, blended the NBM10 percent with the CONSALL for sfc temps late Sat thru Sun. Based on the expected nely winds, a coastal front would likely develop across sern LI and possibly into sern CT, adding another layer to the temp complexity. This boundary should delineate a mainly all rain event from snow or a mixed event. The low is progged to get around 999 by 12Z Sun per the GFS, but there is some model spread in the intensity as well. The GEM appears to be the deepest, getting down to around 988. This signals that a big wind event is not expected attm. The deepest low soln would likely yield peak gusts around 40kt for sern areas. For snowfall, in general this looks like a 4-8 inch with locally higher amounts sys where it remains all snow N and W of NYC, 3-6 most of the area, and 2-4 or less much of LI and the ern CT coast. Again this is all subject to change, with a track to the N bringing more rain and a track further S beginning to limit pcpn amounts. Will add a mention in the HWO for the 4-8 inch zone. Most of the area should change over to periods of mainly light snow on Sun as the low pulls away. Dry by Sun ngt, and remaining dry thru Mon ngt with a 1030s high pres ridge passing thru the area. Should be cold Mon ngt with this setup, especially if there is any snow on the ground. The next storm is late Tue thru Wed. The models have been consistent with this event even this far out. A 970s low tracking W of the region is the current prog. This would produce a high wind event, along with some hvy rainfall. In addition, there could be some fzra across the interior at the onset late Tue into Tue ngt. The models may be having a difficult time handing any CAD with the sys. The MEX at MGJ is close to 15 degrees warmer than the MEX for highs on Tue. Trended the fcst colder, particularly across the interior, as a result.
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&& .AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
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A cold front approaches from the west tonight, passing through the region late Thursday morning into early afternoon. Mainly VFR. Patchy brief MVFR cigs possible this evening, best chances at KSWF. NW/WNW winds back more westerly by late day before lightening to around 5 kt tonight. Frontal passage will increase the flow late Thu AM and veer NW, speeds 15-20kt G25kt in the afternoon. A few gusts may exceed 30 kt. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments may be needed this evening for brief MVFR ceilings. Timing of wind shift and gusts may be off by an hour or two. Isolated gusts at or above 30 kt after 18Z Thu. OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY... Late Thursday: Mainly VFR. NW winds 15 kt G20-25kt. Gusts diminish overnight. Friday: VFR. NW winds G20kt possible for the AM push. Saturday: VFR becoming IFR or lower Sat ngt in snow and/or rain. Increasing E/NE winds. Sunday: Rain/snow ending as snow. IFR or lower possible. Winds becoming N. Monday: Becoming VFR. 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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Conditions will remain below SCA levels tonight into early Thursday as a weak pressure gradient will be across the waters as one weak low passes to the north, and another passes to the south. As colder air moves in behind the northern system`s cold front, and high pressure builds to the west, with the southern system deepening, northwest winds and gusts will increase quickly Thursday to SCA levels across all the forecast waters. And ocean seas will then build to SCA levels Thursday night. The potential for marginal gale force gusts in the ocean waters has diminished and will no longer mention in the HWO. A SCA has been posted for all the waters beginning Thursday afternoon. Conditions will quickly improve late Thursday night as high pressure builds in from the west, and will the advisory across all the waters by 11Z Friday. There is a chance that SCA gusts continue into early Friday morning across the eastern ocean, and possibly eastern Long Island Sound, and the advisory may be extended. Once SCA conditions end no hazards are expected through the remainder of Friday. Gales are possible over the weekend, especially on the ocean, as low pres tracks S and E of the area. The best window is Sat ngt into Sun. Winds and seas subside Sun ngt and Mon. Significant impacts are possible late Tue.
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&& .HYDROLOGY...
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No hydrologic impacts are expected thru this weekend attm. Impacts possible for late Tue into Wed with deep low pres passing W of the area.
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&& .OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory from 2 PM Thursday to 6 AM EST Friday for ANZ331-332-335-338-340-345-350-353-355.
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&& $$ SYNOPSIS...JMC/MET NEAR TERM...MET SHORT TERM...MET LONG TERM...JMC AVIATION...DR MARINE...JMC/MET HYDROLOGY...JMC/MET