Winter 2024-2025 Summary – Eighth Sunniest on Record

Blue Hill Observatory Winter (December-February) 2024-2025 Summary: 

Winter 2024-2025 was cool with average precipitation, much less snowfall, and much more sunshine than expected. The approximated 24-hour mean temperature for the season of 28.8 deg F was 1.3 degrees warmer than the 1891-2020 130-year average for winter, and it was 0.9 degrees cooler than the 1991-2020 30-year average. The average maximum temperature of 36.3 deg F was 1.0 degrees cooler than the 30-year normal, and the average minimum temperature of 21.3 deg F was 0.4 degrees warmer than the 30-year normal. The season was generally cool with short periods of relatively warm temperatures during the second week of December and the last week of February. The warmest temperature was 62F on December 11th; only six days all winter had a high temperature of 50F or higher. The lowest temperature was 2F on January 22nd. The total precipitation was 13.23 inches, which was 0.66 inches below the 30-year normal. December was the wettest month with 7.58 inches, or more than half of the seasonal total. The largest storm of the season brought 3.44 inches of rain on December 10th-12th, and the calendar day total of 3.38 inches on December 11th was the third wettest day ever observed in December. Other notable storms brought 1.17 inches of liquid equivalent precipitation and 9.4 inches of snow, the largest snowfall of the season, on December 20th, and another storm brought 1.95 inches of precipitation and 4.9 inches of snow, sleet, freezing rain, and rain on February 15th-16th. The total snowfall for December to February was 34.1 inches, which was 15.3 inches below the 30-year average. After Ponkapoag Pond first froze on December 3rd, and Houghton’s Pond first froze on December 15th, both ponds remained frozen at the end of February. The mean wind speed was 13.2 mph, and the prevailing wind direction was from the west-northwest. The highest wind gust was 70 mph from the west-northwest on February 17th following the strong storm the day before. Sunshine was much above average in December and January, and near average in February. Winter sunshine was well above average with 480.1 hours of bright sunshine, or 56 percent of possible, which was eight percent more than the long-term average for winter, and the winter season was the eighth sunniest on record.

BHO Highest Winter (Dec-Feb) Bright Sunshine, hours (1885-86 to 2024-25):

1) 521.1 in 1960-61 [62%]   
2) 502.8 in 1963-64 [59%]   
3) 501.8 in 1967-68 [59%]   
4) 499.0 in 2003-04 [58%]   
5) 487.6 in 1976-77 [58%]   
6) 482.7 in 1979-80 [56%]   
7) 480.8 in 2011-12 [56%]   
8)  480.1 in 2024-25 [56%]   
9) 477.8 in 2000-01 [56%]   

Mike Iacono
Chief Scientist
Blue Hill Observatory