Weekly swim report · August 21, 2026
Idaho swim report
On August 21, 2026 the warmest USGS water reading in Idaho was 75°F at SNAKE RIVER AT WEISER ID; 7 water-related NWS hazards are active.
Warmest water
The 5 warmest of 23 sensors reporting a water temperature in Idaho today. Station names open the official monitoring page.
- #1SNAKE RIVER AT WEISER IDUSGS gauge · 8,740 ft³/s75°F 24°C9 hrs ago
- #2BOISE RIVER NR PARMA IDUSGS gauge · 412 ft³/s73°F 23°C9 hrs ago
- #3SNAKE RIVER AT McDUFF RAPIDS AT CHINA GARDEN IDUSGS gauge · 17,500 ft³/s73°F 23°C8 hrs ago
- #4CLEARWATER RIVER AT OROFINO IDUSGS gauge · 1,360 ft³/s72°F 22°C9 hrs ago
- #5SALMON RIVER AT WHITE BIRD IDUSGS gauge · 3,740 ft³/s71°F 22°C8 hrs ago
Active hazards in Idaho
Alerts cover counties or forecast zones — an alert for an area does not mean every river or beach inside it is affected. Times are local to the issuing office.
- CautionHeat Advisory
A Heat Advisory is in effect for Western Magic Valley; Upper Weiser River; Oregon Lower Treasure Valley.
NWS Boise ID · until Aug 21, 9:00 PM
- CautionHeat Advisory
A Heat Advisory is in effect for Lower Treasure Valley; Upper Treasure Valley.
NWS Boise ID · until Aug 21, 9:00 PM
- CautionHeat Advisory
A Heat Advisory is in effect for Northern Panhandle; Coeur d'Alene Area; Idaho Palouse; Central Panhandle Mountains; Lewiston Area; Lewis and Southern Nez Perce Counties; Northeast Blue Mountains; Lower Garfield and Asotin Counties; Washington Palouse; Moses Lake Area; Upper Columbia Basin; Spokane Area; Northeast Mountains; Okanogan Highlands; Wenatchee Area; Okanogan Valley; Waterville Plateau; Central Chelan County; Western Okanogan County.
NWS Spokane WA · until Aug 21, 10:00 PM
- CautionHeat Advisory
A Heat Advisory is in effect for Arco/Mud Lake Desert; Upper Snake River Plain; Marsh and Arbon Highlands; Franklin/Eastern Oneida Region.
NWS Pocatello ID · until Aug 21, 10:00 PM
- CautionHeat Advisory
A Heat Advisory is in effect for Shoshone/Lava Beds; Lower Snake River Plain; Eastern Magic Valley; Southern Hills/Albion Mountains; Raft River Region; Wood River Foothills.
NWS Pocatello ID · until Aug 21, 10:00 PM
- CautionHeat Advisory
A Heat Advisory is in effect for Bear Lake Valley; Blackfoot Mountains; Big Hole Mountains; Teton Valley; Beaverhead/Lemhi Highlands.
NWS Pocatello ID · until Aug 21, 10:00 PM
- CautionHeat Advisory
A Heat Advisory is in effect for Orofino/Grangeville Region; Lower Hells Canyon/Salmon River Region.
NWS Missoula MT · until Aug 21, 9:00 PM
Where to swim in Idaho
The most-reviewed, well-rated water destinations in Idaho — check each one’s live conditions before you go.
4.8(2,728)Idaho Falls River Walk - Greenbelt Trail
Expansive green space on the banks of the river, offering benches, sculptures & views of the falls.
4.6(2,366)Lava Hot Springs Olympic Swimming Complex
The only facility of its kind in the Intermountain West, this swimming complex in Lava Hot Springs features an Olympic-size pool with 50-meter racing lanes, a 10-meter diving tower, four water slides, and an indoor aquatic center open year-round with a poolside rock climbing wall. Located just four blocks from the town's famous natural hot pools, the complex offers clear, warm water reaching 17 feet deep. The indoor center includes a kiddie water playground and hot tub.
4.6(670)Henrys Lake State Park
585-acre sprawling park includes campsites, hiking trails, fishing & boating, plus native wildlife.
4.8(268)Redfish Lake
Scenic site in the mountains offering fishing, canoeing & kayaking, plus hiking, biking & a lodge.
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Conditions are for general information only and can change quickly. Always judge the water in person and follow posted advisories and local guidance before swimming or paddling.