Fairbanks December 2011

In Fairbanks the average temperature was 4.0°F, a very substantial positive deviation (+8.1°F) from the December's long term mean. As November had been much too cold, the unexpected warmth was a welcomed event. Actually, the mean monthly temperature for December was warmer than the mean temperature for November. Furthermore, the minimum temperature for December of -36°F, measured on the last 2 days of the month, was 5°F warmer than the November minimum of -41°F on the 17th. December 2012 tied 1963 as the 10th warmest on record. Generally speaking, the first 3 weeks of the month were much warmer than would be expected, while the last week was below normal. The maximum temperature of the month occurred on the 4th with a balmy temperature, for Interior Alaska in winter, of +47°F. A mean temperature for the day was 37°F, a rare event, as mean daily temperatures above freezing are infrequent in winter. No new record absolute high or low temperatures were observed. Precipitation in December was 0.95" water-equivalent, 48% above the expected value of 0.64" and snowfall at 12.2" was only very slightly above normal. Wind speed averaged a slight 2.8 mph, a low value typical for winter in Interior Alaska. The highest gust was 51 mph on the 5th. Cloud cover was high with a mean monthly value of 80%. This is not surprising as cloudy days are in winter on average warmer than clear ones due to weak winter solar radiation. Hence, the substantially above normal temperatures would be an indication of higher than expected cloud cover.