weather in hyannis port, mass.
Hyannis Port 10 Day Weather. 1  Monday:The Hyannis Port forecast for Aug 15 is 79 degrees and Sunny. There is 55 percentage chance of rain and 3 mph winds from the West-Southwest.  Tuesday:The Hyannis Port forecast for Aug 16 is 81 degrees and Patchy light rain in area with thunder.