Text files containing the raw weather data recorded from sensors on the roof of the main AT&T lab building in Cambridge are available from the links below. Each file contains the half-hourly readings recorded during a single day. If there is no link for a given date, then no weather data was recorded for that day. The entire archive of raw weather data text files is also available as a single gzipped tar file.

Historical weather data is also available in monthly graphical form and as annual and monthly summary statistics.

Note that there are some inaccuracies in the historical humidity and dewpoint readings before October 1998, in the rainfall readings for July and August 2001 and from time to time throughout 2005, and in several readings in July 2006.