Kootenay Lake — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Kootenay Lake, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Kootenay Lake today is 15.7°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 |
|---|---|---|---|
| SEP 14 | 16.9°C | 16.8°C | |
| SEP 15 | 16.7°C | 16.8°C | |
| SEP 16 | 16.6°C | 16.8°C | |
| SEP 17 | 15.8°C | 16.8°C | |
| SEP 18 | 15.5°C | 16.8°C | |
| SEP 19 | 15.3°C | 16.8°C | |
| SEP 20 | 15.1°C | 16.8°C | |
| SEP 22 | 16.8°C | 15.8°C | |
| SEP 23 | 16.8°C | 15.8°C | |
| SEP 24 | 16.8°C | 15.9°C | |
| SEP 25 | 16.8°C | 15.9°C | |
| SEP 26 | 16.8°C | 16.0°C | |
| SEP 27 | 16.8°C | 16.0°C | |
| SEP 28 | 16.8°C | 16.1°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 | 2°C | 5°C |
| February | 0°C | 3°C | 6°C |
| March | 0°C | 3°C | 7°C |
| April | 0°C | 5°C | 11°C |
| May | 4°C | 10°C | 16°C |
| June | 7°C | 14°C | 18°C |
| July | 15°C | 20°C | 25°C |
| August | 17°C | 19°C | 24°C |
| September | 11°C | 17°C | 23°C |
| October | 7°C | 12°C | 16°C |
| November | 3°C | 6°C | 11°C |
| December | 0°C | 3°C | 7°C |
Kootenay Lake: Water Temperature by Location
Kootenay Lake: Weather Forecast
September 22
September 23
September 24
September 25
September 26
Location & Local Information
Kootenay Lake, one of the largest natural lakes in British Columbia, stretches through the scenic Kootenay region between the Selkirk and Purcell Mountains. Fed by snowmelt and mountain streams, the lake remains relatively cool throughout the year. In early spring, after the ice and snow have melted, surface temperatures average around 39–45°F (4–7°C). By late May and June, the water warms to about 52–59°F (11–15°C). During midsummer, particularly in July and August, the surface temperature can reach 63–68°F (17–20°C) in the shallower bays and near popular beaches such as those in Nelson or Kaslo. In deeper sections of the lake, the temperature remains much cooler year-round. As autumn approaches, the water gradually cools again, dropping below 55°F (13°C) by late September.
Swimming in Kootenay Lake is allowed and popular during the summer months when air temperatures are high and the water is at its most comfortable. The clear, clean water and beautiful mountain setting make it ideal for recreation, with several accessible beaches and campgrounds along its shores. However, because of the lake’s size and depth, the water can still feel brisk, especially away from the shore. Most visitors enjoy short swims or relaxing near the beaches during July and August, when the combination of sunshine and mild water provides the best swimming conditions.