Snowfall events can transform landscapes, creating stunning winter scenes, but sometimes, they deliver truly astonishing amounts of snow. These extreme occurrences highlight the variability and intensity of winter weather, and the specific conditions required for such remarkable accumulations.
The World Record Single Snowfall
The greatest 24-hour snowfall officially recorded occurred in Silver Lake, Colorado, between April 14 and 15, 1921. During this period, 75.8 inches (193 centimeters) of snow accumulated. While an unofficial 77-inch measurement in Montague Township, New York, in January 1997 was disallowed due to inconsistent procedures, Silver Lake remains the record. A single storm at Mount Shasta Ski Bowl, California, deposited 189 inches (4.8 meters) of snow over six days from February 13-19, 1959.
North American Snowfall Records
North America holds several significant snowfall records, particularly for seasonal and multi-day accumulations. The highest seasonal snowfall ever recorded globally occurred at Mount Baker, Washington, during the 1998-99 winter season, totaling 1,140 inches (95 feet). This surpassed the previous record of 1,122 inches set at Mount Rainier, Washington, in the 1971-72 season. For a 12-month period, Paradise at Mount Rainier National Park recorded 1,224.5 inches (102 feet) between February 1971 and February 1972. The deepest snowpack ever measured in North America reached 451 inches (37.5 feet) at Tamarack, California, in March 1911.
Global Snowfall Extremes
Beyond North America, other regions experience extraordinary snowfall. The greatest natural snow depth ever recorded was on Mount Ibuki, Japan, where observers measured 465.4 inches (38.8 feet) on February 14, 1927. Tsukayama, Japan, received 68.2 inches (173 centimeters) of 24-hour snowfall from December 30-31, 1960. Europe’s 24-hour record is 67.8 inches (172 centimeters), which fell in Bessans, French Alps, over 19 hours on April 5-6, 1959. Coastal areas of Japan, such as Takada, are known for high annual snowfall, with estimates ranging from 1,200 to 1,500 inches in the Japanese Alps.
How Snowfall Is Measured
Accurately measuring snowfall, especially extreme amounts, requires specific techniques and presents challenges. The primary method uses a snowboard, a flat, white surface typically 16×16 or 24×24 inches, placed in an open, flat area away from obstructions. A ruler is inserted vertically into the new snow until it touches the board, and the depth is read to the nearest tenth of an inch. After each measurement, the snowboard is cleared to record only new snowfall.
Challenges arise from factors like wind drift, snow compaction, and melting. Snow density also varies, with the snow-to-liquid ratio ranging from 5:1 for wet snow to 50:1 for fluffy snow. Manual measurements are often preferred over automated sensors, as human observers can better account for these variables. Observers also measure total snow depth and the liquid equivalent of the snow.