Observatory Reaches 99F on Third Day of Heatwave

After reaching a high temperature of 91F on June 22nd and 94F on June 23rd, 2025, the heatwave reached its third day on Tuesday, June 24th when the temperature soared to a high of 99F at the Observatory on the summit of Great Blue Hill. This reading not only surpassed the record for the date… Read More »

Spring 2025 Summary – Tied for Fourth Warmest on Record

Blue Hill Observatory Spring (Mar-May) 2025 Summary:  Spring 2025 temperature and precipitation were well above average with much less snowfall and less sunshine than expected. The approximated 24-hour mean temperature for spring of 49.0 deg F was 4.1 degrees warmer than the 1891-2020 130-year average for the season, and it was 2.6 degrees warmer than… Read More »

May 2025 Summary – Eighth Wettest on Record

Blue Hill Observatory May 2025 Summary: May 2025 was warmer and much wetter than average with much less sunshine than expected. The approximated 24-hour mean temperature for the month of 57.4 deg F was 1.9 degrees warmer than the 1891-2020 130-year average for May, and it was 0.7 degrees warmer than the 1991-2020 30-year average.… Read More »

April 2025 Summary – Seventh Warmest on Record

  Blue Hill Observatory April 2025 Summary: April 2025 was much warmer than average with below average precipitation and snowfall. The approximated 24-hour mean temperature for the month of 49.3 deg F was 4.4 degrees warmer than the 1891-2020 130-year average for April, and it was 2.6 degrees warmer than the 1991-2020 30-year average. April… Read More »

March 2025 Summary – Warmer Than Average

Blue Hill Observatory March 2025 Summary: March was much warmer than normal, with average precipitation and record low snowfall. The approximated 24-hour mean temperature for the month of 40.2 deg F was 5.7 degrees warmer than the 1891-2020 130-year average for March, and it was 4.4 degrees warmer than the 1991-2020 30-year average. The month… Read More »

State of the Climate at Blue Hill Observatory: 1885-2024

This report is an updated summary of the extensive climate records of the Blue Hill Observatory that focuses on the daily climate data for several key parameters over the entire period of record. This document is also available as a downloadable PDF file.