Lake-effect snow is produced during cooler atmospheric conditions when a cold air mass moves across long expanses of warmer lake water. The lower layer of air, heated by the lake water, picks up water vapor from the lake and rises through colder air. The vapor then freezes and is deposited on the leeward (downwind) shores.
The city of Chicago is located in northern Illinois, United States, at the south western tip of Lake Michigan. It sits on the Saint Lawrence Seaway continental divide at the site of the Chicago Portage, an ancient trade route connecting the Mississippi River and the Great Lakes watersheds.
The climate of Chicago is classified as hot-summer humid continental with hot humid summers and cold, occasionally snowy winters. All four seasons are distinctly represented: Winters are cold and often see snow with below 0 Celsius temperatures and windchills, while summers are warm and humid with temperatures being hotter inland, spring and fall bring bouts of both cool and warm weather and fairly sunny skies. Annual precipitation in Chicago is moderate and relatively evenly distributed, the driest months being January and February and the wettest July and August. Chicago's weather is influenced during all four seasons by the nearby presence of Lake Michigan.
Tug Hill, sometimes referred to as the Tug Hill Plateau, is an upland region in northern New York state, notable for heavy winter snows. The Tug Hill region is east of Lake Ontario, north of Oneida Lake, and west of the Adirondack Mountains. The region is separated from the Adirondacks by the Black River Valley.
Castle Peak is a mountain in California's Sierra Nevada near I-80, Donner Pass, and the Nevada border. It is in the Tahoe National Forest not far off the Pacific Crest Trail, and adjacent to Castle Pass. It was originally named Mount Stanford by the Whitney Survey of 1860–74.
The climate of Salt Lake City, Utah features cold and snowy winters, hot and dry summers, and modest to light seasonal rainfall. Lying in the Salt Lake Valley, the city is surrounded by mountains and the Great Salt Lake. Under the Köppen climate classification, Salt Lake City has either a Mediterranean climate (Csa) or dry-summer continental climate (Dsa) depending on which variant of the system is used, though it borders on a cold semi-arid climate (BSk) due to the city's relatively low precipitation.
Milwaukee has a humid continental climate, with four distinct seasons and wide variations in temperature and precipitation in short periods of time. The city's climate is also strongly influenced by nearby Lake Michigan, which creates two varying climates within the Milwaukee area. The Urban heat island effect also plays a role in the city's climate, insulating it from winter cold, but keeping it cooler in spring and summer.
Chemult is an unincorporated community and census-designated place in Klamath County, Oregon, United States, on U.S. Route 97 near the drainage divide between the Klamath and Columbia Rivers. Chemult has a population of about 80 people. Chemult's elevation is 4,764 feet (1,452 m).
Kirkwood Mountain Resort is a ski resort in Kirkwood, California, south of Lake Tahoe. The resort focuses on skiing and snowboarding in the winter and hiking and mountain-biking in the summer.
The characteristics of United States rainfall climatology differ significantly across the United States and those under United States sovereignty. Summer and early fall bring brief, but frequent thundershowers and tropical cyclones which create a wet summer and drier winter in the eastern Gulf and lower East Coast. During the winter, and spring, Pacific storm systems bring Hawaii and the western United States most of their precipitation. Low pressure systems moving up the East Coast and through the Great Lakes, bring cold season precipitation to from the Midwest to New England, as well as Great Salt Lake. The snow to liquid ratio across the contiguous United States averages 13:1, meaning 13 inches (330 mm) of snow melts down to 1 inch (25 mm) of water.
It is very rare for snow to fall in the U.S. state of Florida, especially in the central and southern portions of the state. With the exception of the far northern areas of the state, most of the major cities in Florida have never recorded measurable snowfall, though trace amounts have been recorded, or flurries in the air observed few times each century. According to the National Weather Service, in the Florida Keys and Key West there is no known occurrence of snow flurries since the European colonization of the region more than 300 years ago. In Miami, Fort Lauderdale, and Palm Beach there has been only one known report of snow flurries observed in the air in more than 200 years; this occurred in January 1977. In any event, Miami, Fort Lauderdale, and Palm Beach have not seen snow flurries before or since this 1977 event.
According to the Köppen climate classification, most of Western Oregon has a warm-summer Mediterranean climate, which features warm, dry summers, and wet winters with frequent overcast and cloudy skies. Eastern Oregon falls into the cold semi-arid climate, which features drier weather.
Thompson Pass is a 2,600 foot-high gap in the Chugach Mountains northeast of Valdez, Alaska. It is the snowiest place in Alaska, recording 500 inches (1,300 cm) of snow per year on average. In the winter of 1952–1953, 974.1 inches (2,474 cm) of snow fell—the most ever recorded in one season at one location in Alaska. It is not the most snow ever recorded in one season at one location anywhere in the fifty states as that record belongs to Mount Baker Ski Resort at 1140 inches in 1998-99. The pass also holds the Alaska record for the most snow in a single day: 62 inches (160 cm) fell on December 29, 1955.
Global storm activity of 2008 profiles the major worldwide storms, including blizzards, ice storms, and other winter events, from January 1, 2008 to December 31, 2008. A winter storm is an event in which the dominant varieties of precipitation are forms that only occur at cold temperatures, such as snow or sleet, or a rainstorm where ground temperatures are cold enough to allow ice to form. It may be marked by strong wind, thunder and lightning, heavy precipitation, such as ice, or wind transporting some substance through the atmosphere. Major dust storms, Hurricanes, cyclones, tornados, gales, flooding and rainstorms are also caused by such phenomena to a lesser or greater existent.
The 2013–14 North American winter was one of the most significant for the United States, due in part to the breakdown of the polar vortex in November 2013, which allowed very cold air to travel down into the United States, leading to an extended period of very cold temperatures. The pattern continued mostly uninterrupted throughout the winter and numerous significant winter storms affected the Eastern United States, with the most notable one being a powerful winter storm that dumped ice and snow in the Southeastern United States and the Northeastern United States in mid-February. Most of the cold weather abated by the end of March, though a few winter storms did affect the Western United States towards the end of the winter.
The 2014–15 North American winter was frigid and prolifically wintry, especially across the eastern half of North America in the months of January–March. The season began early, with many places in North America experiencing their first wintry weather during mid-November. A period of below-average temperatures affected much of the contiguous United States, and several records were broken. An early trace of snowfall was recorded in Arkansas. There were greater accumulations of snow across parts of Oklahoma as well. A quasi-permanent phenomenon referred to as the polar vortex may have been partly responsible for the cold weather. Temperatures in much of the United States dropped 15 to 35 °F below average by November 19, following a southward "dip" of the polar vortex into the eastern two-thirds of the country. The effects of this dip were widespread, bringing about temperatures as low as 28 °F (−2 °C) in Pensacola, Florida. Following a significant snowstorm there, Buffalo, New York received several feet of snow from November 17–21. In addition, significant winter weather occurred throughout the season, including a major blizzard that struck the Northeastern United States at the end of January, another blizzard that affected much of the Northern United States days later in early February, and several significant snow events paired with very frigid temperatures for much of February.
The November 26 – December 3, 2019 North American blizzard was a major winter storm from the Rocky Mountains to the Northeast as well as a record-breaking windstorm along the West Coast. It occurred the week of American Thanksgiving, hampering travel for millions across the United States.
In mid-January 2020, a complex system of winter storms that crossed North America, bringing heavy snowfall and high winds to Atlantic Canada and the northern United States between 15 and 18 January. At least one person was killed, in California, while at least one went missing, in Newfoundland. The person who went missing in Newfoundland was later found dead. Another two people died in Newfoundland after shoveling snow, although the connection to the storm is unclear. The winter storm caused historic blizzard conditions in many areas, particularly Atlantic Canada.
The climate of Seattle is temperate, classified in the warm-summer (in contrast to hot-summer) subtype of the Mediterranean zone by the most common climate classification although some sources put the city in the oceanic zone. It has cool, wet winters and warm, dry summers, covering characteristics of both. The climate is sometimes characterized as a "modified Mediterranean" climate because it is cooler and wetter than a "true" Mediterranean climate, but shares the characteristic dry summer and the associated reliance upon cooler-season precipitation. The city is part of USDA hardiness zone 9a, with surrounding pockets falling under 8b.
