Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 020253 AFDOKX Area Forecast Discussion National Weather Service New York NY 953 PM EST Mon Mar 1 2021 .SYNOPSIS... An Arctic front will pass this evening, producing windy and cold conditions through Tuesday. High pressure will then dominate through the week. Low pressure will pass well to the southeast on Sunday, while high pressure returns on Monday. && .NEAR TERM /THROUGH TUESDAY/... The Arctic front is moving through the area and the wind gusts will continue to increase as it passes. Gusts should be fairly persistent overnight and through the morning. With the frontal passage and in its wake are scattered snow showers, which should mainly be in the form of flurries with a rapidly drying boundary layer due to strong cold air advection. Flurries and snow showers should be very few and far between and brief as they are moving very quickly. The wind advy was still warranted based on the latest progs. There should be an initial surge of winds with the front tngt, then perhaps a slight slackening early in the mrng before they pick up again by 14Z. The NAM in particular keeps 50-55 kt H85 winds in til late aftn. With a deeply mixed atmosphere, the wind advy was extended a few hours to 4 pm. Dry wx on Tue with PW around a tenth of an inch. The NBM was used for low/high temps tngt and Tue, with minor adjustments. Wind chills tngt will drop into the single digits for LI and NYC, and will dip blw zero in spots north of there. Wind chills on Tue will not get out of the teens and lower 20s. && .SHORT TERM /TUESDAY NIGHT/... A mid lvl wave passes N of the region Tue ngt. Any snow with this is progged to remain across VT and upstate NY. Dry wx is expected for the CWA. Winds aloft decrease, and the loss of diurnal heating will further allow for sfc winds and gusts to diminish. There could be enough mixing to prevent ideal radiational cooling. In addition, some mid and high lvl cloudiness is suggested in the time heights. As a result, the NBM was used for temps, which more closely resembled the NAM MOS as opposed to the much colder GFS MOS. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... A deep closed low aloft will retrograde slowly W across eastern Canada through the end of the week, while upper ridging persists from the Rockies into central Canada. Quasi-zonal flow aloft over the eastern states to start will send sfc low pressure well to the south on Wed, then become more amplified through Sat, sending Canadian high pressure with dry and progressively colder air into the region on a brisk NW flow. Mild temps with highs from the mid 40s to mid 50s on Wed will only reach the lower/mid 40s on Thu and the 30s on Fri. Weak return flow as a lobe of the sfc high breaks off and sets up just off the coast should bring slight moderation for Sat, with highs in the upper 30s and lower 40s. The closed low across Canada should begin to weaken beginning Sat, allowing the ridge to the west to slowly build eastward to the Plains states, while a Pacific disturbance undercuts the ridge and enters the base of the longwave trough, with sfc low pressure developing in the Gulf of Mexico on Sat and then passing well to the SE on Sunday, though perhaps not as far SE as model forecasts. Given the dominance of the trough and the position of the ridge to the west, do not expect this low to get very close to the coast, and only 1 out of 51 12Z EPS members showed precip getting to the coast. Allowed a little extra wiggle room for the low to cut in more closely than the op and ensemble forecasts as is often the case in this scenario, but even still that would only warrant slight chance PoP on Sunday for Long Island and SE CT. At any rate, windy and continued cold wx expected in the wake of this departing sys on Mon, with highs only in the 30s. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... An Arctic front is moving through the terminals now. High pressure then builds to the west through Tuesday morning and slides to the south Tuesday afternoon. VFR conditions through the overnight and on Tuesday. NW winds 25-30 kt gusting around 40kt. Occasional gusts as high as 45 kt possible overnight. Winds and gusts begin to diminish Tuesday morning and may be a few kt higher than currently forecast. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... NW wind gusts may be briefly near 45 kt tonight. Wind gusts Tuesday morning may be a few kt higher than currently forecast, possibly near 40 kt especially in the morning. .OUTLOOK FOR 03Z TUESDAY THROUGH SATURDAY... .Tuesday night...VFR. Diminishing NW winds 10-15kt. .Wednesday through Saturday...VFR. NW winds gusting 20-30kt possible Thu. Detailed information, including hourly TAF wind component forecasts, can be found at: http:/ && .MARINE... Strongest winds and higher seas are holding off til cold fropa later this evening, still gale warning remains in effect for all waters. There could be a few isold gusts to storm force, particularly the ern zones. Some areas of light freezing spray are possible overnight and Tue as well. Low tides should approach blowout lvls during the times of low tide Tue mrng. The guidance indicated lvls would be marginal, so an advy was not issued attm. The gales diminish Tue ngt, with a SCA likely needed for most areas for the rest of the ngt, and for the eastern ocean waters on Wed. SCA conds likely for most if not all the waters from late day Thu into Fri night or early Sat morning as NW flow increases with a reinforcing shot of colder air. Can`t totally rule out gales on the outer ocean waters, but frequent gusts up to 30 kt appear more likely attm. && .HYDROLOGY... No hydrologic impacts anticipated attm. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...Wind Advisory until 4 PM EST Tuesday for CTZ005>012. NY...Wind Advisory until 4 PM EST Tuesday for NYZ067>075-078>081- 176>179. NJ...Wind Advisory until 4 PM EST Tuesday for NJZ002-004-006- 103>108. MARINE...Gale Warning until 6 PM EST Tuesday for ANZ330-340-345-350-353- 355. Gale Warning until 4 PM EST Tuesday for ANZ335-338. && $$ SYNOPSIS...JMC/BG NEAR TERM...JMC/BG/MW SHORT TERM...JMC LONG TERM...BG AVIATION...MW MARINE...JMC/BG HYDROLOGY...JMC is the U.S. government's official web portal to all federal, state and local government web resources and services.