Major Nor’easter Brings Record Snow to Observatory

GOES-16 visible satellite image at 9 AM EDT on 13 March 2018.
A powerful coastal storm developed to the south of New England during the night of March 12th, and snow began across the area shortly after midnight on March 13th. It quickly became heavy snow, and Blue Hill Chief Observer, Kaitlin Geagan, measured 5.8 inches on the summit at 7 AM EST with heavy snow in progress and with the wind gusting to 50 mph at that time. Initially the snow was wet and heavy, but after 7 AM, the temperature dropped a couple of degrees and the snow became lighter. Near blizzard conditions continued throughout the morning as bands of heavy snow moved through. The peak gust during the storm was 60 mph from the N at 8:30 AM EST, and the visibility has been 1/4 mile or less. At the 1 PM EST observation, an additional 9.2 inches of snow were measured, bringing the storm total through that time to 15.0 inches as moderate to occasionally heavy snow and blowing and drifting snow continued. The storm total liquid equivalent precipitation through 1 PM EST on the 13th was 1.63 inches. After 1 PM, an additional 8.0 inches of snow and 0.57 inches of liquid equivalent precipitation was measured through the end of the storm bringing the storm totals to 23.0 inches of snow and 2.20 inches of melted precipitation. The average snow to water ratio for the storm was 10.5:1, though the snow ratio increased during the storm from about 7:1 during the first few hours (wetter snow) to 14:1 during the last hours of the storm (drier snow). The calendar day snowfall for the 13th established a new record for the date, surpassing 10.0 inches set in 1993 during the famous “Storm of the Century”, which brought its heaviest snows further inland. The 23.0 inches of snow was also a new calendar day record for March and the third highest for any month of the year. Monthly snowfall for March has climbed to 40.1 inches through 7 AM EST on the 15th, which already makes this month the fifth snowiest March on record.
BHO Greatest March Snowstorms, inches (1885-2018):
1) 30.3 on 3-5 Mar, 1960
2) 30.0 on 31 Mar – 1 Apr, 1997
3) 29.8 on 6-8 Mar, 2013
4) 23.0 on 5-7 Mar, 2001
   23.0 on 13 Mar 2018
6) 19.5 on 19-20 Mar, 1956
7) 17.8 on 15-16 Mar, 1967
8) 17.5 on 20-22 Mar, 1958
9) 16.9 on 11-14 Mar, 1939
10) 15.4 on 29-30 Mar, 1984
BHO Greatest March Calendar Day Snowfalls, inches (1885-2018):
1) 23.0 on 13 Mar, 2018
2) 18.0 on 8 Mar, 2013
3) 17.6 on 19 Mar, 1956
4) 17.3 on 4 Mar, 1960
5) 15.5 on 6 Mar, 2001
6) 15.0 on 31 Mar, 1997
7) 13.5 on 29 Mar, 1984
8) 13.0 on 5 Mar, 1891
9) 12.8 on 3 Mar, 1960
10) 12.3 on 24 Mar, 1956
BHO Greatest Snowstorms, inches (1885-2018):
1) 38.7 on 24-28 Feb 1969
2) 30.8 on 26-28 Jan 2015
3) 30.3 on 3-5 Mar 1960
4) 30.1 on 6-7 Feb 1978
5) 30.0 on 31 Mar – 1 Apr 1997
6) 29.8 on 6-8 Mar 2013
7) 26.6 on 8-9 Feb 2013
8) 24.7 on 17-18 Feb 2003
9) 24.3 on 5-7 Dec 2003
10) 23.0 on 5-7 Mar, 2001
    23.0 on 13 Mar, 2018
BHO Greatest Calendar Day Snowfalls, inches (1885-2018):
1) 27.4 on 24 Feb 1969
2) 25.2 on 27 Jan 2015
3) 23.0 on 13 Mar 2018
4) 20.3 on 12 Dec 1960
5) 20.0 on 17 Feb 2003
6) 19.0 on 20 Jan 1978
7) 18.6 on 16 Feb 1958
8) 18.4 on 29 Dec 1945
9) 17.6 on 19 Mar 1956
10) 17.5 on 26 Dec 1909
BHO Greatest March Monthly Snowfall, inches (1885-2018):
1) 52.0 in 1956
2) 42.2 in 1916
3) 41.4 in 2001
4) 41.0 in 1967
5) 40.1 in 2018 (through 7 AM on the 15th)
6) 37.8 in 2013
7) 35.5 in 1993
8) 33.9 in 1960
9) 30.6 in 1958
10) 29.0 in 1890