Spider Lake Water Temperature
Spider Lake in Iron County, Wisconsin averages about 73°F at the surface in summer — warmest in Jul (~76°F) and coldest in May (~48°F). These are typical values by month, not a live reading.
Typical water temperature by month
Typical surface water temperature by month, from 10 field readings (2024–2026) via the EPA Water Quality Portal. Months with too few readings are left blank.
Is Spider Lake warm enough to swim?
Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Want more than temperature? Spider Lake scored B on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.
Water temperatures at nearby Wisconsin lakes
Summer average ~73°F
Summer average ~74°F
Summer average ~73°F
Typical monthly temps
Summer average ~73°F
Summer average ~74°F
Explore water temperatures
Where to stay near Spider Lake
Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Spider Lake — live availability and prices.
Top-rated places to stay near Spider 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 Spider Lake?
Get lake water-quality report cards plus the best cabin & lodging deals near Spider Lake — straight to your inbox. No spam, unsubscribe anytime.
Frequently asked questions
What is the water temperature of Spider Lake?
Spider Lake has a typical summer surface temperature of about 73°F. It is usually warmest in July (around 76°F) and coldest in May (around 48°F). These are typical values by month from 10 EPA Water Quality Portal field readings (2024–2026), not a live reading.
When is Spider Lake warmest?
Surface water at Spider Lake is typically warmest in July, reaching about 76°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 Spider Lake warm enough to swim?
At its typical summer peak of about 73°F, Spider Lake rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.
Where does this Spider 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 — 10 readings from 1 monitoring station between 2024 and 2026. 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.