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Flathead River

Flathead River Current Water Temperature and Forecast

On this page, you will find comprehensive information about the water temperature in Flathead River, including current readings, historical data and trends, monthly averages, as well as weather forecasts and upcoming temperature predictions. We find every spot where you can swim and tell you what the water temperature is there today and throughout the year.

Current Water Temperature in Flathead River

55°F

TODAY

61°F

YESTERDAY

60°F

A WEEK AGO

As of today, the minimum water temperature in the Flathead River ranges from 54°F (12°C) to 60°F (15°C). The water is significantly warmer, and swimming becomes possible for most people. However, caution may still be required for prolonged stays in the water, as extended exposure can cause discomfort. This is a suitable temperature range for short swims and for those accustomed to cooler water. For more comfortable swimming, it is recommended to use proper gear.

It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.

Analysis, Historical Data, and Forecast of Water Temperature

Water Temperature Chart for Flathead River Over the Last 30 Days

Today the water temperature in Flathead River is lower than the same day in previous years. The water temperature range here in June is from 50°F to 72°F. The water temperature has decreased over the past 7 days but has increased over the past month.

The forecasted water temperature values for Flathead River are presented in the table below.

The actual water temperature values near the shore may differ by a few degrees from the stated values. For the development of the forecast, we use our own mathematical model that takes into account the current water temperature changes, historical data, and key weather trends, including wind strength and direction, and air temperature in each specific region.

Daily Water Temperature Chart

DateCurrentAverageForecast
Jun 1360°F61°F
Jun 1460°F61°F
Jun 1561°F61°F
Jun 1661°F61°F
Jun 1761°F61°F
Jun 1860°F61°F
Jun 1961°F61°F
Jun 2055°F61°F
Jun 2161°F55°F
Jun 2261°F56°F
Jun 2361°F56°F
Jun 2461°F56°F
Jun 2561°F57°F
Jun 2661°F57°F
Jun 2761°F57°F
Jun 2861°F57°F
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast

Water Temperature Ranges in Flathead River by Month

January

MinimumAverageMaximum
34°F41°F48°F

February

MinimumAverageMaximum
34°F41°F48°F

March

MinimumAverageMaximum
32°F42°F52°F

April

MinimumAverageMaximum
34°F47°F61°F

May

MinimumAverageMaximum
39°F55°F70°F

June

MinimumAverageMaximum
50°F61°F72°F

July

MinimumAverageMaximum
63°F68°F75°F

August

MinimumAverageMaximum
63°F71°F73°F

September

MinimumAverageMaximum
52°F64°F66°F

October

MinimumAverageMaximum
46°F56°F61°F

November

MinimumAverageMaximum
37°F47°F61°F

December

MinimumAverageMaximum
37°F40°F46°F

Monthly Water Temperature Histogram for Flathead River

Water Temperature in Cities and Towns on Flathead River

Columbia Falls
United States (Montana)
54°F
Kalispell
United States (Montana)
56°F
Polson
United States (Montana)
61°F

Flathead River Weather

JUNE 21

45°F / 63°F
moderate drizzle

rain: 81% | wind: 17 mph

JUNE 22

43°F / 61°F
light drizzle

rain: 76% | wind: 7 mph

JUNE 23

41°F / 73°F
overcast

rain: 63% | wind: 14 mph

JUNE 24

46°F / 77°F
light drizzle

rain: 43% | wind: 12 mph

JUNE 25

46°F / 82°F
mainly clear

rain: 14% | wind: 14 mph

Water Temperature in Flathead River: General Trends and Swimming Opportunities

Source Confluence of North Fork and Middle Fork Flathead River
• location Rocky Mountains
• elevation 3,120 ft (950 m)
Mouth Clark Fork
• location Montana
• elevation 2,484 ft (757 m)
Length 158 mi (254 km)

The Flathead River, located in northwestern Montana, is a pristine waterway known for its clear waters and stunning surroundings, including Glacier National Park. Its water temperature is significantly influenced by snowmelt from nearby mountains, keeping the river cold for much of the year. During spring and early summer, temperatures often hover between 40°F and 50°F (4°C–10°C), making the water brisk and refreshing. By mid to late summer, in slower sections or areas exposed to the sun, water temperatures can reach up to 60°F–70°F (15°C–21°C), providing more comfortable conditions for recreational activities.

Swimming in the Flathead River is possible during the warmer months, especially in calmer areas like river bends or designated swimming spots near campgrounds and parks. However, the river’s strong currents and cold water make it more suited for activities like floating, kayaking, and paddleboarding. For those looking to swim, it’s best to stick to shallow, still sections and always exercise caution due to the river’s varying depths and flow rates. The Flathead River offers a unique opportunity to enjoy Montana’s natural beauty while cooling off in its refreshing waters.

Geographical Location of Flathead River

Nearby Rivers

Frequently Asked Questions About Flathead River and its Water Temperatures

What is the current water temperature in Flathead River?

The water temperature today in Flathead River ranges from 54°F (12.3°C) to 61°F (16.0°C).

What is the water temperature in Flathead River during the summer months?

The average water temperature in Flathead River during the summer months is typically between 65°F to 71°F (19°C to 21°C), and it can reach up to 75°F (24°C) at its warmest. However, in some years, the temperature may exceed this range.

What is the water temperature in Flathead River in May?

The average water temperature in Flathead River in May ranges from 46°F to 70°F (8°C to 21°C).

What is the water temperature in Flathead River in September?

The average water temperature in Flathead River in September is typically between 52°F to 66°F (11°C to 19°C).

Where does Flathead River flow?

Flathead River flows through United States (Montana), Canada (British Columbia).

Is it possible to swim in the Flathead River?

Yes, it is possible to swim in the Flathead River. However, one should always be mindful of the river's current and potential wildlife.