January 2020 Summary – Eighth Driest and Ninth Warmest on Record
Blue Hill Observatory January 2020 Summary:
January was generally very warm with much less precipitation and snowfall than average. The 24-hour adjusted mean temperature for the month of 32.8 deg F was 7.1 degrees warmer than the 120-year average for January and 6.6 degrees warmer than the 1981-2010 30-year average. The month ranked as the ninth warmest January on record and the warmest since 2006. The average maximum temperature of 40.6 deg F was 6.8 degrees warmer than the 30-year mean, and it was also the ninth warmest on record. The average minimum temperature of 25.9 deg F was 8.8 degrees warmer than the 30-year mean and also the ninth warmest. The highest temperature for the month reached 68F on the 12th, which tied the warmest temperature ever observed in January previously set on January 26th, 1950, and it surpassed the previous record for the date of 60F set in 2018. This very warm day followed a day with a record high maximum of 65F and a daily record high minimum of 46F on the 11th. The lowest temperature for the month was 8F on the 18th. Only seven days during the month were colder than average, while there were 14 days that were ten degrees or more warmer than average. Precipitation totaled 1.46 inches, which was nearly three inches less than the long-term 120-year average and the 30-year mean. This amount ranked as the eighth driest for any January on record. The greatest precipitation in 24 hours was 0.57 inches on the 25th. Snowfall totaled only 4.2 inches, which was about 13 inches less than the 30-year mean. The greatest snowfall in 24 hours was just 3.0 inches on the 18th-19th. The mean wind speed for January was 12.8 mph, which tied for the second lowest on record for January, and the prevailing wind direction for the month was from the west. The monthly peak gust was 60 mph from the south-southwest during the very warm weather on the 12th. January sunshine was slightly higher than average with 139.8 hours or 49 percent of possible, which was three percent more than the long-term mean.
BHO Warmest January 24-Hour Adjusted Mean Temperature, deg F (1886-2020):
1) 35.6 in 1913
2) 35.0 in 1932
3) 34.6 in 1937
4) 33.9 in 2006
5) 33.8 in 1933
33.8 in 1950
33.8 in 1990
8) 33.5 in 2002
9) 32.8 in 2020
10) 32.7 in 2017
BHO Warmest January Average Maximum Temperature, deg F (1886-2020):
1) 44.3 in 1913
2) 42.9 in 1937
3) 42.2 in 1932
42.2 in 1950
5) 42.0 in 1933
6) 41.7 in 1990
7) 41.5 in 2006
8) 40.9 in 2002
9) 40.6 in 2020
10) 39.9 in 1890
BHO Warmest January Average Minimum Temperature, deg F (1886-2020):
1) 28.7 in 1932
2) 28.0 in 2002
3) 27.7 in 1913
4) 27.2 in 1937
5) 26.9 in 2006
6) 26.6 in 1990
7) 26.5 in 1933
8) 26.4 in 2017
9) 25.9 in 2020
10) 25.6 in 1995
BHO Lowest January Precipitation, inches (1886-2020):
1) 0.89 in 1955
2) 0.97 in 1980
3) 1.00 in 1989
4) 1.07 in 1970
5) 1.25 in 1981
6) 1.31 in 1985
7) 1.42 in 2013
8) 1.46 in 2020
9) 1.72 in 2004
10) 1.80 in 1922
BHO Lowest January Mean Wind Speed, mph (1886-2020):
1) 12.2 in 2001
2) 12.8 in 2011
12.8 in 2020
4) 13.1 in 2009
5) 13.3 in 1984
Mike Iacono
Chief Scientist
Blue Hill Observatory
