NOAA News || NOAA Home Page

August 2, 1999 — It's official—Mt. Baker, Wash., has set a new record for the most snowfall ever measured in the United States in a single season, NOAA reported today.

The Mt. Baker Ski Area in northwestern Washington State reported 1,140 inches of snowfall for the 1998-99 snowfall season. The figure was scrutinized by the National Climate Extremes Committee, which is responsible for evaluating potential national record-setting extreme events. The committee, composed of experts from NOAA, the American Association of State Climatologists, and a regional expert from the Western Regional Climate Center, made a unanimous recommendation to the director of NOAA's National Climatic Data Center to accept the figure.

"In accepting the validity of the 1,140 inches of snowfall at Mt. Baker, the National Climatic Data Center recognizes that a new record has been set," said Tom Karl, director of the center. "The previous U.S. seasonal snowfall record was 1,122 inches, set during the 1971-1972 snowfall season at Mt. Rainer/Paradise, a station located at 5,500 feet on the slopes of Mt. Rainer, about 150 miles south of Mt. Baker."

Snowfall can be extremely difficult to measure accurately because it settles, melts, and during times of wind, drifts from place to place. The committee reports that the measurements met snowfall observation standards and practices prescribed by the National Weather Service, and were thus considered to be an accurate depiction of snowfall amounts that fell.

"The measurement frequency was once a day; a flat surface was used to measure daily snowfall amounts; and a snow stake for snow depth measurement was also in place," said Raymond Downs, an observations standards expert on the committee. "Both snowfall and snow depth were measured in acceptable locations. The bottom line is the observations were taken in a manner that meets official observation standards."

Robert Leffler, team leader for the evaluation, said, "Committee members voted to recognize the amount as a new U.S. record because of several factors. These include acceptable snowfall measurement methods, detailed record-keeping, and other corroborative evidence such as independent snow data from other sources, eyewitness accounts, and unusual damage to trees and structures resulting from the crushing weight of the deep snow pack and avalanches."

The Mt. Baker Ski Area is located at an elevation of 4,200 feet, nine miles northeast of the summit of the Mt. Baker volcano. The snowfall season is for the period from July 1, 1998, through June 30, 1999. The committee was concerned only with national records for the United States. However, this total also stands as a world record for a verifiable amount.

The heavy snowfalls normally experienced in the Cascade Mountains of Washington State are the result of several factors. Winter is naturally the wettest season as the west-to-east planetary circulations expands southward and strengthens in speed, with storms striking the Pacific Northwest every few days. Air laden with moisture after its journey across the Pacific is forced to ascent the Cascade Range, dropping abundant precipitation. Freezing levels average about 4,000 feet over the winter months, so that near this altitude snowfall amounts increase very rapidly with just small increases in elevation. This season, a moderately strong La Niña pattern is credited with accentuating this stormy pattern, with a much higher frequency of wet and cold weather systems affecting especially the area from the Cascade Range westward. Freezing levels remained abnormally consistently low throughout the winter.