Bull Frog Lake Water Temperature
Bull Frog Lake in Cook County, Illinois averages about 76°F at the surface in summer — warmest in Aug (~79°F) and coldest in Oct (~60°F). These are typical values by month, not a live reading.
Typical water temperature by month
Typical surface water temperature by month, from 45 field readings (2010–2022) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Bull Frog Lake warm enough to swim?
Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Want more than temperature? Bull Frog Lake scored F on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.
Water temperatures at nearby Illinois lakes
Summer average ~78°F
Summer average ~72°F
Summer average ~80°F
Summer average ~69°F
Summer average ~77°F
Summer average ~75°F
Explore water temperatures
Where to stay near Bull Frog Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Bull Frog Lake — live availability and prices.
Top-rated places to stay near Bull Frog Lake
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 Bull Frog Lake?
Get lake water-quality report cards plus the best cabin & lodging deals near Bull Frog Lake — straight to your inbox. No spam, unsubscribe anytime.
Frequently asked questions
What is the water temperature of Bull Frog Lake?
Bull Frog Lake has a typical summer surface temperature of about 76°F. It is usually warmest in August (around 79°F) and coldest in October (around 60°F). These are typical values by month from 45 EPA Water Quality Portal field readings (2010–2022), not a live reading.
When is Bull Frog Lake warmest?
Surface water at Bull Frog Lake is typically warmest in August, reaching about 79°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 Bull Frog Lake warm enough to swim?
At its typical summer peak of about 76°F, Bull Frog Lake rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Where does this Bull Frog 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 — 45 readings from 2 monitoring stations between 2010 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.