Lethbridge — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Lethbridge, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Lethbridge today is 16.4°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 |
|---|---|---|---|
| SEP 14 | 18.8°C | 15.9°C | |
| SEP 15 | 18.2°C | 15.9°C | |
| SEP 16 | 18.3°C | 15.9°C | |
| SEP 17 | 17.4°C | 15.9°C | |
| SEP 18 | 17.1°C | 15.9°C | |
| SEP 19 | 16.9°C | 15.9°C | |
| SEP 20 | 16.6°C | 15.9°C | |
| SEP 22 | 15.9°C | 16.4°C | |
| SEP 23 | 15.9°C | 16.4°C | |
| SEP 24 | 15.9°C | 16.3°C | |
| SEP 25 | 15.9°C | 16.3°C | |
| SEP 26 | 15.9°C | 16.3°C | |
| SEP 27 | 15.9°C | 16.3°C | |
| SEP 28 | 15.9°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 | 2°C | 5°C |
| February | 0°C | 2°C | 5°C |
| March | 0°C | 3°C | 5°C |
| April | 0°C | 5°C | 11°C |
| May | 4°C | 8°C | 15°C |
| June | 7°C | 14°C | 18°C |
| July | 15°C | 18°C | 23°C |
| August | 17°C | 19°C | 24°C |
| September | 11°C | 16°C | 21°C |
| October | 7°C | 12°C | 16°C |
| November | 3°C | 6°C | 11°C |
| December | 0°C | 3°C | 6°C |
Lethbridge: Weather Forecast
September 22
September 23
September 24
September 25
September 26
Location & Local Information
The major natural waterway in Lethbridge is the Oldman River, which is a cold, mountain-fed river. Due to its glacial origins and high flow rates, the water remains consistently cold. Even in the peak summer months, the surface temperature rarely rises above the range of 17∘C to 20∘C (63∘F to 68∘F), which is cold enough to induce cold shock. In the winter, the water is near freezing, typically ranging from 0∘C to 5∘C (32∘F to 41∘F), with parts of the river freezing over.
Swimming in the Oldman River is strongly discouraged and highly dangerous due to the combination of hazards. The City of Lethbridge warns that the cold, fast-moving water is generally not suitable for swimming, and the river's high volume creates strong, unpredictable currents and undertows. For safer swimming, nearby Keho Lake, a man-made irrigation reservoir, is often used. Its shallow nature allows it to warm up significantly in summer, with surface temperatures typically ranging from 19∘C to 21∘C (66∘F to 70∘F), making it a popular swimming spot. However, Keho Lake frequently faces Blue-Green Algae (Cyanobacteria) advisories in the late summer, which warn against water contact due to potential toxins.