Grand Isle water temperature by month

Swimmable from April through November.

Month by month

Month Typical Feels
January 59° brisk
February 64° brisk
March 69° refreshing
April 74° perfect
May 81° bath-warm
June 86° bath-warm
July 89° bath-warm
August 89° bath-warm
September 85° bath-warm
October 78° perfect
November 71° refreshing
December 63° brisk

The year at a glance

swimmable 50° 60° 70° 80° 90° 100° 89° 59° JFMAMJJASOND January: typically 59° — brisk February: typically 64° — brisk March: typically 69° — refreshing April: typically 74° — perfect May: typically 81° — bath-warm June: typically 86° — bath-warm July: typically 89° — bath-warm August: typically 89° — bath-warm September: typically 85° — bath-warm October: typically 78° — perfect November: typically 71° — refreshing December: typically 63° — brisk

The water right now

Typically about 78° in October — perfect.

from the Grand Isle station, about 3 miles away

perfect

bath-warm 80° and up perfect 72–79° refreshing 65–71° brisk below 65° 78° typical for October

Louisiana's only drive-to barrier island town. The water carries river silt year-round, so it reads warm and looks brown — that is the normal color here, not a bad day.

About this reading

The Grand Isle station sits in an inlet; surf-zone water can run a few degrees off this reading.

Reading from the Grand Isle station, about 3 miles away.

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