Deadmans Basin Reservoir — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Deadmans Basin Reservoir, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Deadmans Basin Reservoir today is 17.4°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 60°F (15°C) to 65°F (18°C). The water is comfortable for most people, making it an ideal range for water sports enthusiasts. The temperature does not cause significant discomfort, and swimming will be pleasant for the majority. However, it's important to remember that prolonged exposure to the water can still lead to cooling, so it's essential to monitor the time spent in the water, especially for children or elderly people. 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 |
|---|---|---|---|
| JUN 2 | 13.8°C | 14.0°C | |
| JUN 3 | 16.4°C | 14.0°C | |
| JUN 4 | 16.4°C | 14.0°C | |
| JUN 5 | 16.7°C | 14.0°C | |
| JUN 6 | 17.2°C | 14.0°C | |
| JUN 7 | 17.6°C | 14.0°C | |
| JUN 8 | 17.8°C | 14.0°C | |
| JUN 10 | 14.0°C | 17.2°C | |
| JUN 11 | 14.0°C | 17.1°C | |
| JUN 12 | 14.0°C | 16.9°C | |
| JUN 13 | 14.0°C | 16.7°C | |
| JUN 14 | 14.0°C | 16.6°C | |
| JUN 15 | 14.0°C | 16.4°C | |
| JUN 16 | 14.0°C | 16.2°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 | 4°C | 6°C |
| February | 1°C | 4°C | 7°C |
| March | 1°C | 5°C | 9°C |
| April | 0°C | 6°C | 12°C |
| May | 4°C | 11°C | 18°C |
| June | 9°C | 14°C | 19°C |
| July | 16°C | 19°C | 22°C |
| August | 17°C | 19°C | 22°C |
| September | 13°C | 16°C | 19°C |
| October | 4°C | 11°C | 17°C |
| November | 2°C | 7°C | 11°C |
| December | 2°C | 5°C | 7°C |
Deadmans Basin Reservoir: Water Temperature by Location
Deadmans Basin Reservoir: Weather Forecast
June 9
June 10
June 11
June 12
Location & Local Information
Deadmans Basin Reservoir in Montana typically has cold water year-round, with surface temperatures varying by season and by depth. In summer the surface commonly warms to roughly 55–70°F (13–21°C) on warm afternoons, though deeper water remains much colder. During spring melt and into early fall surface temperatures are often in the 40–55°F range (4–13°C). In winter the reservoir approaches freezing conditions, with surface temperatures near 32–39°F (0–4°C) and ice cover possible at higher elevations. Like many reservoirs, it stratifies in summer so temperatures drop sharply below the surface, and localized shallow bays can be a few degrees warmer than the main basin.
Swimming opportunities depend on management, access and safety rather than water temperature alone. Recreational swimming is commonly possible where the reservoir and shoreline are managed for public use, but specific areas may be restricted because of dam operations, water-quality concerns, private land, or seasonal hazards. Even where allowed, the cold water poses risks of cold shock and hypothermia and submerged hazards and boat traffic can make swimming unsafe. Visitors should check local regulations and signage, use caution around sudden drop-offs, and limit time in the water to reduce cold-related risks.