During December, every state across the contiguous U.S. had above-average monthly average temperatures. The lack of cold air outbreaks and large winter storm systems limited snow cover and depth for many locations across in the country. In the West, where several storms brought heavy precipitation, the warm temperatures caused a majority of the precipitation to fall as rain, even at higher elevations. According to NOAA's National Snow Analysis, at the beginning of December, 22.8 percent of the contiguous U.S. had snow on the ground — the Cascades, Sierra Nevada Mountains, parts of the Great Basin, the Central and Northern Rockies, the Northern Plains and Upper Midwest, and most of the interior Northeast. The monthly snow cover extent dipped mid-month reaching a minimum on the 19th at 17.5 percent of the Lower 48 having snow on the ground. The snow cover peaked at the end of month at 42.7 percent — much of the Western United States, Great Plains, parts of the Upper Midwest, and northern New England.

Northern hemisphere snow cover anomalies
U.S. December Snow Cover Extent Anomalies
Source: Rutgers Global Snow Lab

According to NOAA data analyzed by the Rutgers Global Snow Lab, the monthly snow cover extent across the contiguous U.S during December was 980,000 million square miles, about 201,000 square miles below the 1981-2010 average. This was slightly larger than the record large November extent and ranked as the 14th smallest December snow cover extent in the 49-year satellite record for the contiguous United States. This was the smallest December snow cover extent for the Lower 48 since 2011. Above-average snow cover was observed across the Central and Northern Plains and parts of the Northeast. Below-average snow cover was observed across much of the West, Midwest, and the Mid-Atlantic. The Alaska December snow cover extent was slightly above average and ranked as the 26th largest on record; it should be noted that 20 of the 49 years in the period of record have total snow coverage for Alaska. The December 2014 Alaska snow cover extent was slightly less than total state coverage.


Citing This Report

NOAA National Centers for Environmental Information, Monthly National Snow and Ice Report for December 2014, published online January 2015, retrieved on March 28, 2024 from https://www.ncei.noaa.gov/access/monitoring/monthly-report/snow/201412.