Hungry Horse Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Hungry Horse Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Hungry Horse Reservoir today is 19.5°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. 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.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| AUG 17 | 20.0°C | 21.0°C | |
| AUG 18 | 20.0°C | 21.0°C | |
| AUG 19 | 19.3°C | 21.0°C | |
| AUG 20 | 19.4°C | 21.0°C | |
| AUG 21 | 19.4°C | 21.0°C | |
| AUG 22 | 19.4°C | 21.0°C | |
| AUG 23 | 20.5°C | 21.0°C | |
| AUG 24 | 20.7°C | 21.0°C | |
| AUG 25 | 21.0°C | 19.6°C | |
| AUG 26 | 21.0°C | 19.7°C | |
| AUG 27 | 21.0°C | 19.7°C | |
| AUG 28 | 21.0°C | 19.8°C | |
| AUG 29 | 21.0°C | 19.9°C | |
| AUG 30 | 21.0°C | 20.0°C | |
| AUG 31 | 21.0°C | 20.0°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 0°C | 1°C | 4°C |
| February | 0°C | 3°C | 5°C |
| March | 1°C | 3°C | 6°C |
| April | 1°C | 4°C | 7°C |
| May | 3°C | 9°C | 15°C |
| June | 11°C | 15°C | 18°C |
| July | 14°C | 18°C | 21°C |
| August | 17°C | 21°C | 25°C |
| September | 15°C | 18°C | 20°C |
| October | 8°C | 12°C | 16°C |
| November | 3°C | 6°C | 9°C |
| December | 0°C | 2°C | 5°C |
Hungry Horse Reservoir: Water Temperature by Location
Hungry Horse Reservoir: Weather Forecast
August 25
August 26
August 27
August 28
August 29
Location & Local Information
Hungry Horse Reservoir, fed by snowmelt in the Rocky Mountains of northwest Montana, stays relatively cool year-round. Seasonal surface temperatures typically range from near freezing in winter—around 32°F (0°C) where ice forms in protected bays—to the low 40s–50s °F (4–13°C) in spring as snowmelt pours in. By early to midsummer, surface readings in sheltered, shallow areas can warm into the upper 50s to mid-60s °F (14–19°C) on sunny days, while deeper and faster-flowing sections usually remain colder. Come fall the water cools back toward the 40s–50s °F (4–13°C). Local conditions such as depth, inflow from the South Fork Flathead River, dam releases and recent weather cause notable variability, and bottom or outflow areas can be much colder than the surface.
Swimming at Hungry Horse Reservoir is generally permitted in the recreation areas, but it is often limited by safety and environmental factors rather than formal prohibition. Cold temperatures even in summer increase risk of cold-water shock and hypothermia, and hazards such as steep drop-offs, submerged debris, heavy boat traffic and fluctuating levels near the dam or inflow channels make some spots unsafe. Visitors are advised to use designated swim areas where present, wear flotation devices when appropriate, and exercise caution because the reservoir’s chilly, variable water can catch swimmers unprepared.