We told you about this before, but now 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, theCommerce Department’s National Oceanic and Atmospheric Administration reported today.

The Mt. Baker Ski Area in northwestern Washington State reported 1,140inches of snowfall for the 1998-99 snowfall season. The figure wasscrutinized by the National Climate Extremes Committee, which is responsible for evaluatingpotential 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 tothe 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 recordhas 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 accuratelybecause it settles, melts, and during times of wind, drifts from placeto 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 anaccurate depiction of snowfall amounts that fell.

“The measurement frequency was once a day; a flat surface was usedto measure daily snowfall amounts; and a snow stake for snow depthmeasurement was also in place,” said Raymond Downs, an observations standards expert on thecommittee. “Both snowfall and snow depth were measured in acceptablelocations. The bottom line is the observations were taken in a manner that meets officialobservation standards.”

Robert Leffler, team leader for the evaluation, said, “Committeemembers voted to recognize the amount as a new U.S. record because ofseveral factors. These include acceptable snowfall measurement methods, detailed record-keeping, and other corroborative evidence such as independent snow data from othersources, eyewitness accounts, and unusual damage to trees and structures resulting from thecrushing 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. Thesnowfall 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 alsostands as a world record for a verifiable amount.

The heavy snowfalls normally experienced in the Cascade Mountainsof Washington State are the result of several factors. Winter isnaturally the wettest season as thewest-to-east planetary circulations expands southward and strengthens inspeed, with storms striking the Pacific Northwest every few days. Airladen with moisture after itsjourney across the Pacific is forced to ascent the Cascade Range,dropping abundant precipitation. Freezing levels average about 4,000feet over the winter months, so thatnear this altitude snowfall amounts increase very rapidly with justsmall increases in elevation. This season, a moderately strong La NiÒapattern is credited with accentuatingthis stormy pattern, with a much higher frequency of wet and coldweather systems affecting especially the area from the Cascade Rangewestward. Freezing levels remainedabnormally consistently low throughout the winter.