Grand Lake New Brunswick — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Grand Lake New Brunswick, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Grand Lake New Brunswick today is 21.9°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature ranges from 68°F (20°C) to 74°F (23°C). The water is warm and pleasant for swimming, and in this range, one can stay in the water for extended periods without the risk of hypothermia. This is the ideal temperature for relaxation, swimming, and water sports. Families with children, as well as outdoor enthusiasts, will enjoy swimming and time spent in the water. For most people, this is the optimal temperature for a comfortable beach experience. 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 24 | 22.9°C | 21.1°C | |
| AUG 25 | 23.0°C | 21.1°C | |
| AUG 26 | 22.6°C | 21.1°C | |
| AUG 27 | 21.9°C | 21.1°C | |
| AUG 28 | 22.0°C | 21.1°C | |
| AUG 29 | 22.0°C | 21.1°C | |
| AUG 30 | 22.0°C | 21.1°C | |
| AUG 31 | 21.9°C | 21.1°C | |
| SEP 1 | 16.0°C | 21.6°C | |
| SEP 2 | 16.0°C | 21.3°C | |
| SEP 3 | 16.0°C | 21.0°C | |
| SEP 4 | 16.0°C | 20.7°C | |
| SEP 5 | 16.0°C | 20.4°C | |
| SEP 6 | 16.0°C | 20.1°C | |
| SEP 7 | 16.0°C | 19.8°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 | 13°C | 20°C |
| July | 15°C | 20°C | 25°C |
| August | 17°C | 21°C | 26°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 Lake New Brunswick: Water Temperature by Location
Grand Lake New Brunswick: Weather Forecast
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Location & Local Information
Grand Lake, located in central New Brunswick near the Saint John River system, is the largest freshwater lake in the province. Its broad surface and moderate depth cause gradual warming throughout the spring and summer. In early spring, following the ice melt in April, the lake remains quite cold, averaging around 39–45°F (4–7°C). By late May and June, surface temperatures rise to about 54–63°F (12–17°C). During midsummer, from July through August, Grand Lake reaches its warmest period, with surface temperatures typically between 68–75°F (20–24°C) in sheltered bays and shallower areas. In early autumn, the water begins to cool again, dropping below 59°F (15°C) by late September as cooler air returns.
Swimming in Grand Lake is allowed and highly popular throughout the summer months. The lake’s gentle shoreline, sandy beaches, and warm surface water make it one of the best swimming destinations in New Brunswick. Areas such as Minto and Youngs Cove offer accessible beaches and family-friendly conditions, while the calm water is ideal for boating, kayaking, and other recreation. Although the water can feel brisk early in the season, it becomes comfortably warm by July, providing excellent swimming opportunities through early September before temperatures begin to decline again in fall.