March 2021 Summary – Warmer and Drier Than Average and Sunniest on Record

Blue Hill Observatory March 2021 Summary:

March was warmer, drier, less snowy, and much sunnier than average. The 24-hour adjusted mean temperature for the month of 39.2 deg F was 4.7 degrees warmer than the 1891-2020 130-year average for March, and it was 3.4 degrees warmer than the 1981-2010 30-year average. The average maximum temperature of 50.2 deg F was 5.9 degrees warmer than the 30-year mean, and the average minimum temperature of 29.1 deg F was 2.5 degrees warmer than the 30-year mean. The highest temperature observed all month was 71F on the 11th, and the lowest temperature was 10F on the 2nd. March total precipitation was 2.17 inches, which was about two and a half inches less than the long-term 130-year average and three and a half inches less than the 1981-2010 30-year mean. Most of this precipitation fell in two events on the 18th and 28th each amounting to 0.80 inches, and these rainfalls also tied for the greatest amount in 24 hours during March. Total snowfall for the month was a scant 0.2 inches, which was about a foot of snow less than the long-term mean for March, and the month tied for the fourth lowest snowfall on record for the month. The greatest snowfall in 24 hours was 0.1 inches on the 2nd and 14th. The mean wind speed for the month was 14.2 mph, and the prevailing wind direction was from the west-northwest. The monthly peak wind gust was 69 mph from the west-northwest on the 1st, which ushered in a couple of days of Arctic air through the 3rd. With few storms and infrequent clouds during the month, March sunshine was well above average at 243.0 hours, which was 68 percent of the possible bright sunshine and 19 percent more than the long-term average. The monthly sunshine tied with 1915 as the highest on record for March.

BHO Lowest March Snowfall, inches (1886-2021):

1) T in 1921
2) 0.1 in 1979
   0.1 in 2006
4) 0.2 in 1903
   0.2 in 2021
6) 0.3 in 1930
7) 0.4 in 1974

BHO Highest March Bright Sunshine, hours (1886-2021):

1) 243.0 in 1915 [68%]
   243.0 in 2021 [68%]
3) 236.7 in 1946 [66%]
4) 230.1 in 1978 [64%]
5) 215.0 in 2006 [60%]

Mike Iacono
Chief Scientist
Blue Hill Observatory