Six warmest years on record have all occurred since 2012
The December contiguous U.S. temperature was 39.3 degrees F, 6.7 degrees above average, making it the warmest December on record and exceeding the previous warmest December in 2015, according to a report released this week by the National Oceanic and Atmospheric Administration (NOAA).
In the Lake Tahoe area, the National Weather Service (NWS) in Reno maintains records from Tahoe City. 2021 was the 13th warmest on record with a mean temperature of 45.4 degrees F. The warmest mean was in 2014 with a mean temperature of 47.0 degrees F.
For Reno in 2021, the mean temperature was the 6th warmest on record at 56.2 degrees F. The highest was in 2014 with a mean temperature of 57.4 degrees F. All top ten warmest years in Reno have been since 2000.
Ten states — Alabama, Arkansas, Kansas, Louisiana, Mississippi, Missouri, Nebraska, New Mexico, Oklahoma, and Texas — also had their warmest December on record.
These temperatures wrap up a year that is the fourth warmest on record. In 2021 the average contiguous U.S. temperature was 54.5 degrees F, 2.5 degrees above the 20th-century average. Records have been kept for 127-years. The six warmest years on record have all occurred since 2012.
Most of the contiguous U.S. experienced above-average temperatures during 2021. Maine and New Hampshire both had their second-warmest year on record with 19 additional states across the Northeast, Great Lakes, Plains, and West experiencing a top-five year. Temperatures were near average for the year in pockets across the South and Gulf Coast states.
Snowfall during the 2020-2021 snow season was consistently below average across the Sierra Nevada range and parts of the northern Rockies. The 2022 snow season started off with record snowfall at upper elevations of the Sierra Nevada but since December snowfall has been minimal.
Last year, the U.S. experienced 20 separate billion-dollar weather and climate disasters that killed at least 688 people — the most disaster-related fatalities for the contiguous U.S. since 2011 and more than double last year’s number of 262.
More than 7.1 million acres were burned across the western U.S. last year, which was 96% of the 10-year average, NOAA reported. The second-largest fire in California history, the Dixie Fire, consumed nearly 964,000 acres in 2021. Smoke from several large fires created air quality and health concerns throughout much of the season.