609
FXUS61 KOKX 252054
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
354 PM EST Wed Dec 25 2024

.SYNOPSIS...
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High pressure remains in control through Friday. The high slides east of the area Saturday as a warm front approaches into Sunday, with an attendant cold front moving through on Monday. Another frontal system impacts the region into mid next week.
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&& .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
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A midlevel shortwave moves in from the north late tonight. At the surface though, high pressure will continue to build in from the north. With the shortwave, expecting an abundant amount of cirrus to move across the region late tonight into early Thursday. However, there is enough dry air to preclude precipitation. Dry conditions are expected to continue. For the low temperature forecast, used a CONSMOS and NBM blend, which has slightly higher temperatures than MOS alone for most locations. The forecast of slightly higher temperatures is to account for extra clouds to partially limit radiational cooling. The forecast lows range from lower teens to mid 20s.
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&& .SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY/...
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After the shortwave passes south of the region early Thursday, strong mid level ridging expected Thursday afternoon into early Friday. Mid level ridge axis moves overhead early Friday and then shifts east of the region. Some warmer air at 850mb will be moving in Thursday through Friday. Eventually SW flow becomes more established at 850mb for late Thursday night into Friday. At the surface, high pressure remains strong across the local region with MSLP of near 1030mb. The center of the high is north of the area Thursday and then gets more into the local area Thursday night into Friday. Dry weather is expected to continue. Clouds abundant early Thursday are expected to decrease during the day and especially in the afternoon. Mostly clear conditions Thursday night will be followed by an increase in clouds during the day Friday. Regarding temperatures, used a MAV and MET blend for high temperature forecast Thursday. These represent slightly warmer temperatures than the previous day with the warmer air moving in aloft. Highs forecast range mainly from mid 30s to around 40. Warmer air will get mixed down to the surface Thursday. Again using the MAV/MET blend for low temperatures Thursday night. With ridge moving overhead, this should make for mostly clear sky conditions and with light winds, radiational cooling will be efficient. A vast range of lows forecast, from single digits inland to near 30 within NYC. Used a NBM and CONSMOS blend for high temperatures Friday with temperatures ranging more in the upper 30s to near 40. Winds will eventually become more SW but will remain very light, limiting the vertical mixing and thereby adiabatic vertical mixing potential. This will limit how high temperatures will rise in addition to the increase in clouds during the day.
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&& .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
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Becoming milder and unsettled this weekend and early to mid next week with a series of systems traversing the region. Deep layer ridging and surface high pressure shift east and offshore Friday night and Saturday. Meanwhile, a weak mid level shortwave swinging through the Great Lakes will attempt to send a warm front toward the region Saturday into Sunday, returning chances for precipitation. Global guidance has sped up the timing of this system, and PoPs have increased on Saturday as a result. Return surface flow sets up as the high moves offshore, and WAA with SW winds aloft begin to gradually increase temperatures into early next week. Despite a warm nose just above the surface, with cold antecedent conditions, and marginal surface temperatures progged near freezing Saturday morning across the interior, it`s not out of the question a bit of freezing rain could occur with the initial precip, depending on timing. This is a concern primarily north and west of NYC and coastal locales. Otherwise, intermittent light rain is possible Saturday and Saturday night across the region. Warm sector on Sunday keeps conditions drear, and PoPs increase once again with the attendant cold front into Sunday night and Monday. Guidance continues to diverge hereafter, with some members deepening a surface wave nearby along the frontal boundary, enhancing rainfall through Monday. Others are more progressive and lighter with amounts. Either way, an unsettled start early next week, with another frontal system likely to follow into midweek. Capped PoPs at 50% after Monday given the uncertainty, with the national blend largely relied on for this update.
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&& .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... Strong high pressure will remain nearly stationary across the area through Thursday. VFR. Northerly winds less than 10 kt. ...NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty... No unscheduled amendments expected. OUTLOOK FOR 18Z THURSDAY THROUGH MONDAY... Thursday through Saturday AM: VFR. Saturday Afternoon-Sunday: Rain becoming increasingly likely with MVFR/IFR conditions. Chance of LLWS. Monday: Chance of MVFR or lower in rain, mainly in the morning. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n900 && .MARINE...
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With high pressure in control and the pressure gradient remaining weak, winds and seas are expected to remain well below SCA thresholds through Friday. Conditions remain below Small Craft Advisory criteria through Saturday. A frontal system then approaches, and the resultant southeast flow may allow ocean seas to build toward and above 5 ft by late Sunday or Sunday night. Wind gusts up to 25 kt are also possible by Sunday night.
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&& .HYDROLOGY...
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Dry conditions are expected through Friday. There are no hydrologic concerns through early next week.
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&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JM/DR NEAR TERM...JM SHORT TERM...JM LONG TERM...DR AVIATION...DW MARINE...JM/DR HYDROLOGY...JM/DR