Hammonasset Beach State Park water temperature by month

Swimmable from July through September.

Month by month

Month Typical Feels
January 39° brisk
February 38° brisk
March 42° brisk
April 49° brisk
May 57° brisk
June 65° refreshing
July 74° perfect
August 75° perfect
September 72° perfect
October 63° brisk
November 52° brisk
December 43° brisk

The year at a glance

swimmable 30° 40° 50° 60° 70° 80° 75° 38° JFMAMJJASOND January: typically 39° — brisk February: typically 38° — brisk March: typically 42° — brisk April: typically 49° — brisk May: typically 57° — brisk June: typically 65° — refreshing July: typically 74° — perfect August: typically 75° — perfect September: typically 72° — perfect October: typically 63° — brisk November: typically 52° — brisk December: typically 43° — brisk

The water right now

Typically about 63° in October — brisk.

from the New Haven harbor station, about 19 miles away

brisk

bath-warm 80° and up perfect 72–79° refreshing 65–71° brisk below 65° 63° typical for October

The nearest sensor sits back in New Haven harbor, and harbor water runs warmer than the open Sound. Expect the swim off Meigs Point to be a few degrees cooler than this number.

About this reading

The New Haven harbor station sits in the harbor; open-water surf can read a few degrees different.

Reading from the New Haven harbor station, about 19 miles away.

Warm water says nothing about surf, rip currents, or bacteria — check local lifeguard flags and advisories.