Winter 2015-2016 Summary – Warmest on Record

Blue Hill Observatory
Winter 2015-2016 Summary:

The winter (December-February) season began with the warmest December on record and continued generally warmer than average with a few brief cold spells and moderate snowfalls. The 24-hour mean temperature for the winter of 34.9 deg F was 7.6 degrees warmer than the 120-year average for winter and 5.9 degrees warmer than the 1981-2010 30-year average. Each month was warmer than average with December setting a new record for that month with the largest positive temperature departure for any month. The highest temperature for the season was 67F on December 24th, and the coldest temperature was -14F on February 14th. There were 32 days during the season with a high temperature of 50F or higher and eight days with a high temperature of 60F or higher, both of which set a new record.  The liquid equivalent precipitation total for winter was 13.64 inches, which was slightly drier than the 120-year average and slightly wetter than the 1981-2010 mean. Winter snowfall totaled 38.1 inches, which was about five inches less than the long-term mean and about six inches less than the 30-year normal. The largest single snowstorm brought 12.5 inches of mostly heavy, wet snow on February 5th that stuck on the trees and other surfaces for a couple of days making for a brief but beautiful, wintry scene across the area. Nearby Houghton’s Pond first froze on January 5th and thawed on February 25th during heavy rain and strong winds. The pond remained frozen for only 51 days this winter, which was the second shortest freeze duration on record. This interval is about half of the 120-year average period of 99 days that this pond remains frozen. The mean wind speed for the winter months was only 13.5 mph, which was the fourth slowest wind speed for any December-February period on record.  The peak gust during winter was 76 mph from the south, which occurred on a very warm day with heavy rain and thunderstorms on the morning of February 25th. Winter was slightly cloudier than average with 46 percent of the possible bright sunshine being observed, which was one percent less than the 120-year average of 47 percent. Much of this departure was due to December, which was very cloudy, while January and February were slightly sunnier than average.

BHO Warmest Winters, deg F (1885-2016):

1) 34.9 in 2015-2016
2) 34.8 in 2001-2002
3) 34.3 in 2011-2012
4) 32.6 in 1997-1998
5) 32.3 in 1936-1937
    32.3 in 1998-1999

BHO Winter (Dec-Feb) Number of Days with Maximum Temperature 50F or Higher, (1885-2016):

1) 32 in 2015-2016
2) 23 in 1990-1991
3) 22 in 1953-1954
    22 in 1973-1974
5) 21 in 2001-2002

BHO Winter (Dec-Feb) Number of Days with Maximum Temperature 60F or Higher, (1885-2016):

1) 8 in 2015-2016
2) 5 in 1929-1930
    5 in 1953-1954
    5 in 1975-1976
    5 in 1980-1981
    5 in 1994-1995
    5 in 2001-2002

BHO Shortest Houghton’s Pond Freeze Duration, (1885-2016):

1) 38 days, January 16, 2012 – February 23, 2012
2) 51 days, January 5, 2016 – February 25, 2016
3) 54 days, December 31, 1996 – February 23, 1997
4) 56 days, December 28, 2001 to February 22, 2002
    56 days, January 18, 2007 – March 15, 2007
6) 58 days, January 5, 1974 – March 4, 1974
7) 62 days, December 24, 1959 – February 24, 1960

BHO Lowest Winter Mean Wind Speed, mph (1885-2016):

1) 13.1 in 2013-2014
2) 13.3 in 2011-2012
    13.3 in 2014-2015
4) 13.5 in 2015-2016
5) 13.6 in 2007-2008
6) 13.7 in 2004-2005
    13.7 in 2012-2013
8) 13.9 in 2001-2002

Mike Iacono
Chief Scientist
Blue Hill Observatory