Science and data
The Blue Hill record is valuable because it is consistent. Observers on Great Blue Hill have measured the weather from the same summit, with the same care, every day for 141 years. That lets scientists compare a winter today with a winter in the 1890s and trust the difference.
One line for every year of the record. There are no gaps.
Consecutive days observed, February 1, 1885 through August 31, 2026.
Observations taken in FY2026, about three a day, every day.
The year our sunshine record began. It is now the longest in North America.
Years of the record still held in handwritten logbooks.
Where the record goes to work
Chief Scientist Michael Iacono serves on the Commonwealth’s Climate Science Advisory Panel, created by the Healey-Driscoll Administration. The Observatory is working with the Massachusetts Office of Climate Science on the state’s first State of the Climate Report.
The Observatory works under contract with the National Weather Service and is the only privately operated WMO Centennial Observing Station in the United States, part of a small global network of stations recognized for more than a century of consistent observation.
Observatory staff work with professional researchers, volunteers, and students from high school through college to turn historical and ongoing observations into usable knowledge, with current work on temperature change, wind energy, and regional resilience.
Our observers publish daily, monthly, and seasonal climate summaries. NPR, WBUR, the Boston Globe, Eos, and Science Friday have drawn on the record to explain how New England’s weather and climate are changing.
What it takes
Once a day is missed, it is gone for good. A trained observer must be on the summit every day of the year, including weekends, holidays, and storms. That is about 3,700 hours of work a year, and our budget pays for roughly 2,860 of them.
More than 100 years of the record exist only on paper, vulnerable to fire or flood. Digitizing them will let researchers, educators, and the public put the full record to work.
A year keeps daily observations running.
Digitizes the full handwritten record.
A history of firsts
Abbott Lawrence Rotch founded the Observatory in 1885. In 1894, observers lifted weather instruments aloft on kites from the summit, among the earliest steps in upper-air science. That spirit of careful, original measurement still runs the Observatory today.
Every gift helps keep a trained observer on the summit tomorrow, and every day after.
Monthly Skymail, event announcements, and research summaries.
