Deep Lake Water Temperature
Deep Lake in Seminole County, Florida typically sits around 87°F at the surface in September — warmest in Sep (~87°F) and coldest in Dec (~71°F). That is a typical value for the month, not a live reading.
Typical water temperature by month
Typical surface water temperature by month, from 37 field readings (2015–2025) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Deep Lake warm enough to swim?
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? Deep Lake water quality: clarity, algae, phosphorus, depth, fish species, and current advisories, all on one page.
Water temperatures at nearby Florida lakes
Summer average ~87°F
Summer average ~87°F
Summer average ~87°F
Summer average ~87°F
Summer average ~87°F
Summer average ~87°F
Explore water temperatures
Where to stay near Deep Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Deep 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 Deep 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.
Planning a trip to Deep Lake?
Get lake water-quality updates plus the best cabin & lodging deals near Deep Lake — straight to your inbox. No spam, unsubscribe anytime.
Frequently asked questions
What is the water temperature of Deep Lake?
Deep Lake typically sits around 87°F at the surface in September, from 37 EPA Water Quality Portal field readings (2015–2025). That is a typical value for the month, not a live reading.
When is Deep Lake warmest?
Surface water at Deep Lake is typically warmest in September, reaching about 87°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 Deep Lake warm enough to swim?
At its typical summer peak of about 86°F, Deep 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 Deep 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 — 37 readings from 2 monitoring stations between 2015 and 2025. 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.