Alder Lake is a lake in Washington.

What is the water temperature at Alder Lake?

As of August 20, 2026, the water temperature at Alder Lake in Washington is 57°F (14°C), measured by NOAA buoy TCNW1, 34.9 miles away.

How is Alder Lake rated?

Alder Lake in Washington has an average visitor rating of 4.7 out of 5, based on 171 reviews.

What amenities does Alder Lake have?

Visitor-listed amenities at Alder Lake include camping-nearby.

Updated August 13, 2025

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Photo: Close- up of Alder catkins on the ice of Tin Mine Lake, Washington. Near Seattle, Washington. From the Environmental Protection Agencys Project DOCUMERICA collection, "In Praise of Forests". For additional images see Fiche #s 209, 210, 211, 212, and 213. ENTHEOS. January, 1974. by Unknown authorUnknown author or not provided (Public domain) License

Alder Lake

Lake

4.7(171 reviews)

Read reviews

Hot — visit earlycamping-nearby

Seven-mile long reservoir for kayaking & angling with mountain views, plus a campground.

Current water conditions

Water temp

57°F

14°C

Cold water — serious cold-shock risk today. At this temperature, sudden immersion can trigger involuntary gasping and sap a strong swimmer's strength within minutes. Enter slowly, never alone, and consider a wetsuit — or sit this one out.

Live data from NOAA buoy TCNW1 (34.9 mi away), as of Aug 20, 10:30 PM UTC. Conditions are for general information only and can change quickly — always judge the water in person and follow posted advisories before swimming.

Weather at Alder Lake

H: 92° L: 56°

Sunny

92°

Feels like 91°

Precipitation

Humidity

28%

Wind

5 mph

UV Index

Water Conditions:

🏊Perfect for swimming🧴High UV - use sunscreen

12 AM

65°

3 AM

59°

6 AM

56°

9 AM

66°

12 PM

85°

3 PM

92°

6 PM

89°

9 PM

74°

Pack smarter for Alder Lake

Useful gear categories for this kind of water spot. These links open Amazon search results so you can compare current options.

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Inflatable PaddleboardA popular way to explore calm coves and shorelines.

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Life JacketImportant around boats, paddling, and deeper swimming areas.

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Floating CoolerKeeps drinks nearby for swim areas, docks, and boats.

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Waterproof Phone PouchProtects phones around docks, boats, and splashy shorelines.

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Frequently asked questions

Where is Alder Lake?: Alder Lake is a lake in Washington.
What is the water temperature at Alder Lake?: As of August 20, 2026, the water temperature at Alder Lake in Washington is 57°F (14°C), measured by NOAA buoy TCNW1, 34.9 miles away.
Can you swim at Alder Lake?: There is no fixed answer for Alder Lake: whether it is safe to swim there on a given day depends on the water temperature, recent rainfall, and any advisories posted at Alder Lake in Washington. Check current water conditions before you go, and follow posted signs and local guidance.
How is Alder Lake rated?: Alder Lake in Washington has an average visitor rating of 4.7 out of 5, based on 171 reviews.
What amenities does Alder Lake have?: Visitor-listed amenities at Alder Lake include camping-nearby.

Visitor Reviews

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Been here? A quick note helps the next visitor plan their day. Handy things to mention:

Water temperatureCrowds & parkingBest time to goSafety & access

Best Times to Visit

☀️

Right Now

Very warm - visit early morning or evening

🏞️ Lakes Tips:

›Check for boat launch facilities and fees
›Obtain required fishing licenses before arrival
›Be aware of lake-specific regulations and restrictions
›Monitor water quality reports before swimming

Best Seasons:

☀️ Summer (Jun-Aug)🍂 Fall (Sep-Nov)🌸 Spring (Mar-May)

Location & Contact

Washington

Washington None

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