2023–24 North American winter

The 2023–24 North American winter was the warmest winter on record across the contiguous United States, with below-average snowfall primarily in the Upper Midwest and parts of the Northeastern United States. However, some areas, especially in the states of Pennsylvania, New Jersey and New York saw considerably more snow than the previous winter. Notable winter events were also more prevalent across the eastern half of the country this winter, including a series of winter storms in mid-January that brought snow from the South to Northeast states, a period of very cold temperatures across much of the country in mid-to-late January, and a disruptive nor'easter that affected much of the Mid-Atlantic in mid-February. 2 storms have been rated so far on the Regional Snowfall Index (RSI), although none have attained a "Major" rating (Category 3+). A strong El Niño was expected to influence the winter weather patterns across the continent.

Based on the astronomical definition, winter began at the winter solstice, which occurred on December 21, 2023, and ended at the spring equinox on March 19, 2024. Based on the meteorological definition, the first day of winter started on December 1 and the last day was February 29. However, winter storms may occur outside of these limits.

Seasonal forecasts
On October 4, 2023, AccuWeather released their winter prediction. They called for a El Niño; their forecast called for the Southeastern United States and California to be wetter than average, some of which could form severe weather outbreaks. The Midwestern United States was predicted to have higher temperatures and drier conditions than average. AccuWeather notes that cities like Boston, New York City, Philadelphia, and Pittsburgh are expected to have more snowfall than last winter. The predictions for the West Coast were that storms will occur commonly in the winter.

Pre-Thanksgiving storm complex
A winter storm affected Northern New England shortly before U.S. Thanksgiving. Up to 6 in of snow fell in the state of Vermont, with New Hampshire and Maine also recording over 4 in of snow. The snowstorm resulted in 53 car crashes in New Hampshire, with one crash resulting in Interstate 93 shutting down near Littleton. Normal pre-Thanksgiving traffic was expected to be worsened due to the storm. The storm also resulted in 55 flight cancellations. Further south, heavy rain fell in the New York Metropolitan area, with some areas reporting over 3 in. Daily rainfall records were broken on November 22 in Islip, Bridgeport and LaGuardia Airport.

Late November winter storm
A winter storm affected much of the Great Plains shortly after U.S. Thanksgiving. Three people were killed in fatal car crashes along Interstate 80 in Nebraska, where 14 crashes occurred and portions of the highway were shut down. The state of Wyoming also responded to 125 car crashes within a 48-hour period. Lander, Wyoming received their snowiest day since 1999 when 19 in of snow piled up. The second snowiest November day was realized in Topeka and Wichita. Interstate 135 was briefly shut down due to the snow, as was Wichita Dwight D. Eisenhower National Airport. Further east, the city of Chicago recorded 1.8 in of snow on November 26. Further east, lake effect snow fell around Lake Erie, which resulted in a fatal car crash in Pennsylvania, a 20-vehicle pileup near Cleveland and Ontario Highway 403 shutting down. The highest snowfall total was 42.7 in in Highmarket, New York.

Christmas Day blizzard
On Christmas Day, an intensifying low pressure system developing into a blizzard struck the Upper Midwest, dropping more than 12–18 in of snow. Spearfish, South Dakota recorded 14.6 in of snow. Whiteout conditions and strong gusty winds were reported in states like Nebraska and North and South Dakota due to the storm. Blizzard warnings were issued for a large part of Nebraska and South Dakota as well as parts of northern Kansas. The system caused many accidents as a result, including jackknifed semis on eastbound Interstate 80 in Nebraska, forcing a portion of that road to close for several hours. Significant closures also occurred on Interstate 90 in South Dakota and Interstate 70 in Colorado. Badlands National Park was closed due to the blizzard. The storm also caused one fatality on icy roads in Kansas.

Early January nor'easter
A winter storm, that became a nor'easter, affected the Northeastern United States from January 6–7, 2024. Multiple locations in several states, including New Jersey, Pennsylvania and Connecticut recorded 1 ft of snow. 13,000 customers also lost power in Massachusetts. The storm also ended the longest stretch without measurable snow in Harrisburg, Pennsylvania and the longest stretch without 1 in of snow in State College, Pennsylvania. Portions of the Massachusetts Turnpike closed due to snow. In addition, planned construction along the New York Thruway between Orange County and Ulster County was postponed by a week. Despite over 1 ft of snow in Port Jervis, New York, the record snow drought in New York City continued, as Central Park only picked up 0.2 in of snow. Boston measured 3.8 in during the snow event, with 5.6 in of snow in Providence, Rhode Island and 10.4 in of snow in Hartford, Connecticut.

January winter storms
From January 8–19, following a pattern change, four consecutive winter storms affected much of the country with rain, snow, blizzard conditions and flooding.

First storm (January 8–10)
The first winter storm hit the Midwest, Southeast, and East Coast on January 8–10, 2024. Interstate 70 was closed from Watkins, Colorado to the Kansas state line due to the storm. Winds in Colorado gusted up to 80 mph, while winds in New Mexico reached 76 mph. Snow drifts in the Oklahoma Panhandle reached 4-5 ft due to wind and heavy snowfall. In the Eastern United States, many states had over 40,000 customers lose power, with 130,000 power outages in New York and 90,000 power outages in Pennsylvania. Western New York was hit hard, with winds gusting to 74 mph in Dunkirk and 78 mph in Watertown; the National Weather Service's Buffalo office warned in an Area Forecast Discussion that gusts from the southeast descending from Tug Hill could reach "potentially generational" levels. Maine experienced the storm as a "sou'easter", with the strongest winds occurring simultaneously with astronomical hide tide, leading to widespread coastal flooding. Gale-force winds occurred along the coast, especially in the Down East region, further contributing to coastal flooding, erosion, and structural damage.

In total, about 1,350 flights were canceled, more than 8,700 more flights were delayed, about two dozen tornadoes were reported, and at least 6 people died because of the storm, with 2 being winter storm related.

Second storm (January 10–13)
The second system, which brought blizzard conditions to some areas, hit most of the U.S. starting on January 10, 2024, sweeping from the Northwest into the Midwest, Great Lakes area, and the East Coast. Almost every U.S. state became under some form of weather alert.

The storm resulted in blizzard warnings for Oregon and Washington's mountain areas for the first time since 2012. Crater Lake National Park closed due to the winter storm. Following the storm, record cold conditions were observed in Washington, with Seattle observing a low of 13 F, their coldest temperature since 1990. Ski resorts in on Mount Baker closed due to the cold as well. More than 443,000 customers lost power from Oregon to Michigan, with 111,000 outages in Oregon alone. Portions of Interstate 70 in Kansas were closed due to the winter weather. Moline, Illinois recorded their second snowiest day on record on January 12, with 15.4 in of snow. Coastal Maine was once again, for the second time in 4 days, affected by widespread coastal flooding and gale-force winds, leading to structural destruction and coastal bank erosion. Record tide gauge levels of 14.57 ft were recorded in Portland, causing the 2024 Portland Flood. The storm, combined with the January 9th storm, created an estimated usd $70.3 million in damages for the state of Maine, prompting a major disaster declaration to be declared in the state by President Joe Biden.

Nationwide, over 2000 flights were canceled on January 12 and over another 1000 were canceled on January 13. A state of emergency and travel ban was declared in Western New York, forcing the playoff game between the Pittsburgh Steelers and the Buffalo Bills to be postponed from January 14 at 1pm to January 15 at 4:30pm. In addition, an NHL game between the Toronto Maple Leafs and Detroit Red Wings suffered a 52 minute delay. Portions of Queen Elizabeth Way were also closed. Five people died due to the storm: three in Oregon, one person in California, and one in Wisconsin.

Third storm (January 13–16)
The winter storm in Oregon resulted in two fatalities, 161,000 customers losing power, and all MAX Light Rail service being suspended for three days. Winds in the Columbia River Gorge reached 80 mph, with gusts over 50 mph in Portland. Many cities in the Southeastern United States, such as Little Rock, Arkansas and Nashville, Tennessee closed schools. In the Northeastern United States, the storm snapped record long streaks without 1 in of snow in several cities, with a little over 1 in recorded in Atlantic City, 3.3 in of snow in Philadelphia and 4.9 in of snow in Baltimore, with Washington D.C. recording 4.1 in of snow. Central Park reported 1.2 in of snow on January 16, their first inch of snow in a single day since February 13, 2022. The storm total there was 1.6 in.

In total, at least 30 fatalities have been linked to this storm system, including 14 in Tennessee, five in Pennsylvania, three in New York, three in Oregon, and one in Kansas.

Fourth storm (January 16–19)
Right after the previous storm departed the East Coast, another snowstorm affected the Pacific Northwest, with significant ice in Oregon and parts of Washington. Over 80,000 customers in Oregon lost power. Further east, snow squalls led to numerous pileups in Nebraska. Further east, a state of emergency was declared due to the winter storm in the Philadelphia metropolitan area, resulting in hundreds of schools closing, as well as attractions such as National Constitution Center and Elmwood Park Zoo. The winter storm also resulted in speed restrictions on portions of the New Jersey Turnpike. In total, 4.6 in of snow fell in Philadelphia, with around 2-3 in of snow in the Lehigh Valley, up to 6 in of snow in New Jersey and up to 7 in of snow in Delaware. Further south, 4.2 in of snow fell in Baltimore and 3.7 in of snow fell in Washington D.C. The snow in DC led to a ground stop at Ronald Reagan Washington National Airport. Further north, despite a travel advisory in New York City, only 0.4 in of snow fell.

Mid-January cold wave
Freezing temperatures affected campaign events leading up to the Iowa Caucuses on January 15, and could affect turnout in the first contest in the 2024 presidential primaries and caucuses. In addition, the cold temperatures resulted in the 4th coldest NFL game on record between the Kansas City Chiefs and Miami Dolphins, with kickoff temperature being -4 F. Fifteen people were hospitalized due to the cold temperatures during the game. Wind chills following the storm reached as low as -60 F in Montana, and wind chills were still -9 F as far south as Dallas on January 14. On January 13, Dillon, Montana reached an all time record low of -42 F, while Bozeman, Montana recorded their second coldest temperature at -45 F. That same day, Dickinson, North Dakota reached a -70 F wind chill, their coldest since the wind chill formula was updated in 2001, and a -33 F air temperature, a daily record and their coldest temperature since 1990. On January 16, Houston dropped to a daily record low of 19 F. The cold wave and snow that the storm brought with it led to at least 55 fatalities.

Early February Canadian blizzard
A slow-moving significant blizzard affected much of Atlantic Canada from February 2–5, dumping 2–5 ft of snow as the system stalled south of the Canadian Maritimes and Nova Scotia. A peak accumulation of 150 cm was measured in the town of Sydney, Nova Scotia. Blizzard-like conditions occurred across the eastern portions of the region as the system slowly moved east, and schools were closed and many roadside services were suspended during the duration of the storm. Hundreds of 9-1-1 calls were made during the height of the blizzard, particularly in the regions with heavier snowfall and gusty winds.

Early February West Coast atmospheric rivers
A Pineapple Express storm hit the state from February 1 to February 2, 2024, before moving over the United States and settling over the I-25 corridor in Colorado, where heavy snow fell. Another one is expected to hit February 3 and last until February 5, with the National Weather Service calling it "potentially life-threatening." Other news sources estimated that Los Angeles could receive six-months' worth of rain in the 48-hour period, while the Sierra Nevada mountains are generally expected to get 1 to 3 ft of snow, with over 4 ft of snow expected in higher elevations, such as Mammoth Lakes, CA. Parts of the San Bernardino Mountains' foothills could receive 10 to 12 in of rain.

Pre-Valentine's Day nor'easter
A weak area of low pressure developed along the Gulf Coast and trekked northeastwards throughout February 11–12 across the Southeast as the system as a whole continued eastward. At 09:00 UTC, the Weather Prediction Center deemed it necessary to begin issue storm summary bulletins for the winter storm. As the system became a nor'easter and moved offshore on February 13, rapid deepening – known also as "bombing out" – commenced overnight, with the central pressure falling from 991 mb at 09:00 UTC on February 13 to 964 mb at 03:00 UTC on February 14, a drop of 27 mb in 18 hours. As this process commenced during the early morning hours on February 13, precipitation rapidly switched from rain to heavy snowfall along much of the Mid-Atlantic, with rates approaching 1–2 in per hour in the northwestern and northeastern portions of New Jersey and Pennsylvania, respectively, which led to the heaviest snowfall totals of the event in those areas. The nor'easter moved quickly, with precipitation and snowfall ending across the Mid-Atlantic and eventually New England by evening that day; consequently, the WPC terminated storm summary bulletins for the departing nor'easter at 03:00 UTC on February 14.

Many cities in the Mid-Atlantic, particularly New York City, were expected to receive the heaviest snowfall accumulation in at least two years due to the nor'easter, although the storm was notable for being difficult to predict in the aforementioned regions in the hours leading up to the event. Flights were cancelled or delayed across the Mid-Atlantic, and millions spanning from Pennsylvania to Massachusetts were placed under winter storm warnings. Over 175,000 people across the Northeast lost power, due to the heavy wet nature of the snow, and the nor'easter was responsible for at least one death so far as of February 13. Separately, the system dumped at least 1 ft in parts of Texas and Oklahoma causing severe impacts in the region as well.

Mid-February Mid-Atlantic winter storm
A surprise major winter storm began affecting the Mid-Atlantic during the overnight hours of February 16–17. A fast-moving clipper system moved through the Midwest early on February 16, dropping 3–5 in of snow with isolated higher amounts near the cities of St. Louis, Missouri and Kansas City, resulting in Gateway Arch National Park closing at 2 p.m. on February 16. The winter storm moved eastwards into the Ohio Valley where similar accumulations were reported. The main event began later that day as the system approached the Mid-Atlantic states. Frontogenesis occurred spawning a very heavy snowband reminiscent of those in lake-effect snow, which pushed into the eastern regions of Pennsylvania, central New Jersey – including the town of New Brunswick – and the southern parts of Staten Island, New York and western Long Island, just south of New York City. Extreme snowfall rates of 4–5 in per hour occurred in this band, which the Mount Holly National Weather Service (NWS) office described as "serious snowfall rates" and by amateur meteorologists in the region as "historic".

The heaviest snow fell in Center Valley, Pennsylvania, with 13.8 in, with 13 in of snow in Township, New Jersey, 12.1 in in Allentown and 9.9 in of snow in Coney Island, New York. Snowfall in New York City varied heavily, with 6.1 in of snow at John F. Kennedy International Airport and 2 in of snow in Central Park. 2.2 in of snow fell in Baltimore, and 3.5 in of snow fell in Philadelphia. The winter weather resulted in the National Park Service shutting down portions of George Washington Parkway.

Late February–early March blizzard
A major winter storm began to affect the Western United States on February 29, with blizzard conditions and several feet of snow expected in the mountainous regions of the state of California. Blizzard warnings were issued for a majority of the Sierra Mountains, including Lake Tahoe, California. The storm resulted in over 100 mi of Interstate 80 shutting down, and Yosemite National Park was also briefly shut down. The blizzard brought very strong winds to the mountainous regions – a near-record-breaking wind gust of 190 mph was reported at Palisades Tahoe at an elevation of 8700 ft late on March 1.

Late March winter storm
On March 21 and 22nd, the storm brought up to 8 in of snow to the Twin Cities. As the storm moved eastwards, heavy snow fell throughout the Northeastern United States on March 23, particularly in Northern New England and Upstate New York. The heaviest snow accumulation totaled 33.1 in in West Windsor, Vermont, with 29 in of snow in Penobscot, Maine, 28 in of snow in Albany, New Hampshire and 25.6 in of snow in Pawlet, New York. Portions of Interstate 93 closed due to the snow. The snowstorm resulted in 360,000 power outages in the Northeast, with nearly 200,000 in Maine alone. Further south, record rainfall brought flooding to Philadelphia, and shut down portions of the Cross Island Parkway and Fifth Avenue in New York City. The Staten Island Railway was also closed due to the rain. Following the floods, temperatures dropped below freezing, leading to icy patches on roads in the New York metropolitan area.

Northern United States
Many regions, particularly the Upper Midwest, saw their warmest winter on record, which was coupled with below-average snowfall as well. Ice coverage across the Great Lakes was at a record low for the 2023–24 winter, due to a lack of persistent cold air. The Michiana region recorded their 2nd warmest and 4th least snowy winter.

Canada
Several cities experienced one of their warmest winters on record, with little snowfall occurring on Christmas Day. Extreme temperature contrasts occurred in December 2023 and January 2024, with the latter being one of the warmest Decembers on record in Canada, and coldest January in decades across Alberta and British Columbia.