SUMMIT COUNTY — The winter of 2012-2013 cracked the top 20-warmest list, with the average temperature across the lower 48 states well above the 20th century average. Specifically, the average temperature across the contiguous U.S. for December through February was 34.3 degrees, which is 1.9 degrees above average, according to the National Climatic Data Center’s monthly State of the Climate report.
That may not sound like a lot, but consider that 20th century average is just barely above the freezing mark. A jump of almost two degrees above that has huge implications for snow cover, as well as for ice formation on lakes and streams.
February wasn’t quite so warm on its own — at 34.8 degrees the monthly average was 0.8 degrees above the 20th century average, federal climatologists said, adding that precipitation for the month was near the long-term average. Significant snow and rain across parts of the country helped improve drought conditions in the Midwest and Southeast, but dryness persisted across the Central Plains and Mountain West.
Parts of the Mountain West remained cooler than average for the second month in a row, including western Colorado, where numerous locations reported readings between 6 and 10 degrees below average. Crested Butte, for example, reported its second-coolest February on record. The monthly average temperature was only 7.5 degrees, which is 5.9 degrees below average, but still several degrees warmer than the all-time record of 3.9 degrees, set in 1974.
Snowfall picked up a bit in the Rockies, but dry conditions prevailed across the far West, especially in the Sierra Nevada and the Cascades, as well parts of the California coast. Many locations in California and western Nevada reported January-February precipitation totals in the 10 driest on record.
Downtown San Francisco recorded only 1.82 inches of precipitation, the fifth driest January-February in a 163-year record. Nearby, Santa Cruz recorded its driest such period since 1893 with 1.22 inches, while farther north, Ukiah and Eureka, California, saw their second and third driest January-February, respectively. Los Angeles experienced its 15th driest January-February in a 69-year record, with 1.5 inches of rain, just 25 percent of average.
Reno, Nevada reported its driest January – February on record, as the Sierra Nevada snowpack dwindled, with the snow-water equivalent fall to between 60 and 70 percent of normal.
Read the full report here.