Grand River — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in the Grand River, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in the Grand River today is 23.2°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 75°F (23°C) to 79°F (26°C). This is a very comfortable temperature for swimming, and many people can enjoy prolonged stays in the water without feeling cold. The water is pleasantly warm, making it ideal for relaxation and water sports. This temperature range is particularly popular among tourists, as it combines comfort and safety for health. 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 6 | 22.1°C | 19.0°C | |
| AUG 7 | 22.2°C | 19.0°C | |
| AUG 8 | 22.3°C | 19.0°C | |
| AUG 9 | 22.7°C | 19.0°C | |
| AUG 10 | 23.1°C | 19.0°C | |
| AUG 11 | 23.2°C | 19.0°C | |
| AUG 12 | 23.1°C | 19.0°C | |
| AUG 13 | 23.2°C | 19.0°C | |
| AUG 14 | 19.0°C | 23.0°C | |
| AUG 15 | 19.0°C | 22.8°C | |
| AUG 16 | 19.0°C | 22.6°C | |
| AUG 17 | 19.0°C | 22.4°C | |
| AUG 18 | 19.0°C | 22.2°C | |
| AUG 19 | 19.0°C | 21.9°C | |
| AUG 20 | 19.0°C | 21.7°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 | 3°C | 4°C |
| February | 0°C | 3°C | 4°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 | 20°C |
| July | 15°C | 19°C | 24°C |
| August | 17°C | 19°C | 24°C |
| September | 11°C | 16°C | 20°C |
| October | 7°C | 12°C | 16°C |
| November | 3°C | 6°C | 11°C |
| December | 0°C | 3°C | 6°C |
Grand River: Water Temperature by Location
Grand River: Weather Forecast
August 13
August 14
August 15
August 16
August 17
Location & Local Information
Source:
• location Near Dundalk, Ontario
• elevation 525 m (1,722 ft)
Mouth:
• location Lake Erie at Port Maitland
• elevation 174 m (571 ft)
Length 280 km (170 mi)
The Grand River, which flows through Southern Ontario, is a major waterway whose water temperature is heavily influenced by the warm summer air but moderated by its flow. In the winter, the water is near freezing, typically ranging from 0∘C to 5∘C (32∘F to 41∘F), with ice cover in slow-moving sections. During the peak summer months, surface temperatures can warm to a comfortable range, generally between 19∘C and 24∘C (66∘F to 75∘F), making the water suitable for brief recreational contact.
Swimming directly in the main channel of the Grand River is strongly discouraged by the Grand River Conservation Authority (GRCA) and is prohibited within the limits of some cities like Brantford, due to significant safety concerns. The main hazards are the river's currents and unpredictable flows that can change rapidly following rain or dam releases, as well as the danger zones around dams and weirs. The GRCA instead promotes swimming in the many reservoirs and spring-fed quarries along the river system, such as Elora Quarry and Guelph Lake, where beaches and buoyed areas are maintained for public use. All swimming outside of these designated locations is strictly at one's own risk.