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Harbor Isles Lake Water Temperature

Harbor Isles Lake in Pinellas County, Florida typically sits around 88°F at the surface in August — warmest in Jul (~90°F) and coldest in Jan (~64°F). That is a typical value for the month, not a live reading.

Typical in August
88°F
Warm
Summer average
89°F
Warmest (Jul)
90°F
Coldest (Jan)
64°F

Typical water temperature by month

Jan
64°
Feb
68°
Mar
75°
Apr
80°
May
82°
Jun
88°
Jul
90°
Aug
88°
Sep
Oct
78°
Nov
Dec
70°

Typical surface water temperature by month, from 60 field readings (20202022) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Harbor Isles Lake warm enough to swim?

At its summer peak (~89°F): Warm

Very comfortable for swimming. Warm surface water can also favor blue-green algae in nutrient-rich lakes, so check for advisories before you go in.

Want more than temperature? Harbor Isles Lake water quality: clarity, algae, phosphorus, depth, fish species, and current advisories, all on one page.

Where to stay near Harbor Isles Lake

Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Harbor Isles Lake — live availability and prices. Switch the map to Satellite to see the lake and how close each stay is to the water.

Top-rated places to stay near Harbor Isles Lake

Prices for Sep 18–20, 4 adults. Change dates on the map below.

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

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Frequently asked questions

What is the water temperature of Harbor Isles Lake?

Harbor Isles Lake typically sits around 88°F at the surface in August, from 60 EPA Water Quality Portal field readings (2020–2022). That is a typical value for the month, not a live reading.

When is Harbor Isles Lake warmest?

Surface water at Harbor Isles Lake is typically warmest in July, reaching about 90°F. Lake surface temperature lags air temperature by several weeks, so the warmest water usually arrives in mid-to-late summer even though the hottest air can come earlier.

Is Harbor Isles Lake warm enough to swim?

At its typical summer peak of about 89°F, Harbor Isles Lake rates as "warm" for swimming. Very comfortable for swimming. Warm surface water can also favor blue-green algae in nutrient-rich lakes, so check for advisories before you go in.

Where does this Harbor Isles Lake water temperature data come from?

Every temperature on this page is a typical (climatological) value computed from real surface-water field readings collected by state and federal agencies and published through the EPA Water Quality Portal — 60 readings from 3 monitoring stations between 2020 and 2022. They describe what is typical for each month, not the temperature right now.

About this data

Water temperatures are a climatology — the typical value for each month, averaged from real surface-water field readings collected by state and federal agencies and published through the EPA Water Quality Portal. They tell you what to expect, not the temperature at this moment. Actual conditions vary with recent weather, depth, and time of day.