11:30 am – Snow and mixed precipitation has begun to fall across the NYC Tri-State Area as a two-day winter storm moves into the Northeast. December 1 is considered the first day of ‘Meteorological Winter’ – a period of time that lasts until the end of February and is considered the coldest three month period in the Northern Hemisphere.
THE FREEZING LINE
This storm will be characterized by sharp precipitation boundaries over relatively short distances. The difference between coastal and inland locations, or even changes in elevation of only several hundred feet, will dictate both when and how much frozen precipitation will fall and accumulate.
INLAND LOCATIONS (Or above 400 ft elevation) – Winter Storm Warnings. The most inland locations will likely not experience any mixed precipitation at all. Snow accumulations in these areas may exceed one foot. For less inland locations currently under a winter storm warning, a mid-afternoon changeover to mixed precipitation or rain is expected today, with a refreeze and changeover back to snow expected around noon Monday. Among the several inches of snow possible, the threat exists for ice to accumulate on roadways, trees, and power lines. Travel will be significantly more difficult during periods of heavier precipitation this afternoon and evening. A refreeze as well as more snow tomorrow will further complicate travel. Exercise extreme caution on roadways and avoid unnecessary travel if possible.
COASTAL LOCATIONS (Generally less than 400 ft elevation) – Winter Weather Advisories or no winter weather alert. A mix of snow, sleet, freezing rain, and rain will transition to all rain by mid-afternoon today. A transition back to frozen precipitation is expected Monday afternoon. Several inches of snow as well as some ice accumulation are possible. Exercise caution on slick roadways.
Due to the mixed-precipitation nature of this early December storm, any actual snow accumulation will depend on how long snow falls before transitioning to sleet, freezing rain, or rain. Total storm accumulations will likely be impacted by any changeover to rain.
Conditions may vary significantly over relatively short distances. Be prepared for rapidly changing conditions and exercise caution while outdoors and on the road.
The National Weather Service has issued Winter Storm Warnings and Winter Weather Advisories throughout the New York City Tri-State Area. Updated ice accumulation forecasts have indicated a much more significant level of ice accretion for locations to the north and west of the city, making for potentially dangerous roadway conditions Tuesday afternoon as well as setting up the possibility for isolated to potentially widespread power outages going into Tuesday night.
Plan on steady snow developing by mid-morning Tuesday, with the potential for snowfall rates exceeding 1 to 2 inches per hour in the first couple hours of the storm. While the exact timing of the transition from snow to wintry mix (sleet, freezing rain, and snow) depends heavily on specific location, most areas – excluding Long Island, where the transition could occur more rapidly and sooner than elsewhere – will see this changeover around the early to mid-afternoon.
Roadways will become dangerous by early afternoon due to periods of heavy precipitation and ice accretion. Please avoid unnecessary travel during the worst of the storm, with extreme caution on both treated and untreated roadways due to ice, snow, and reduced visibility. Most locations should see conditions rapidly improve Wednesday as temperatures are expected to go above freezing.
Starting late tomorrow afternoon, wintry precipitation can be expected across large swaths of the Metro Area. Locations north and northwest of the city can expect frozen precipitation until early morning Monday, meaning that although it will transition to rain by mid morning in most locations, roads may be icy and slushy. Currently there is a great deal of uncertainty in regard to the temperature Monday morning, which, if are even only a degree below where currently expected, could create an even messier commute.
This is the Third Edition of the NYC Area Week Outlook by Weather360
Monday: A wintry mix in the morning will transition to all rain by the afternoon. Total snow accumulations of up to a couple of inches are possible in some (mainly northern and eastern) portions of the area. Highs will hover around in the low to mid 40’s.
Tuesday: Highs dropping into the low to mid 30’s will be associated with clearing skies, making it seem much more like January than April.
Wednesday: High temperatures will peak in the mid 40’s as skies become increasingly cloudy, due to an incoming low pressure system.
Thursday: Rain associated with a low pressure system moving in from the west will bring in much more seasonable temperatures, with a high in the upper 50’s. This rain could spell the end to winter for many Ski Resorts throughout the Northeast.
Friday: Cooler temperatures along with clearing skies will make for a somewhat more seasonable day.
The Weekend: Highs in the 40’s along with mainly clear skies will make for a brisk, cool, early spring weekend.
In the event of an emergency weather situation, please consult the NWS at weather.gov and/or your local Emergency Management Office.