This data the coastal The Grotto water temperature today, tomorrow and the upcoming days. Besides, you can also get information about the weather and surf forecast, as well as the data on sunrise / sunset and moonrise / moonset at a given point on any given day.
Water temperature in The Grotto today is 18.6°C. Based on our historical data over a period of ten years, the warmest water in this day in the Georgian Bay near The Grotto was recorded in 2012 and was 20.5°C, and the coldest was recorded in 2019 at 17.2°C. Water temperature in The Grotto is expected to drop to 18°C in the next 10 days. September average water temperature in The Grotto is 18°C, the minimum temperature is 14.3°C, and the maximum is 21.1°C.
The swimming season in The Grotto lasts only one month - August. During this month, The Grotto water temperature does not drop below 20°C and therefore suitable for comfortable swimming. The average water temperature in The Grotto in winter reaches 3.2°C, in spring 2.2°C, in summer the average temperature rises to 15.4°C, and in autumn it is 13.4°C.
5 September 2025 |
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today temp |
18.6°C |
4 September 2025 |
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yesterday temp |
18.6°C |
Another important indicators for a comfortable holiday on the beach are the presence and height of the waves, as well as the speed and direction of the wind. Please find below data on the swell size for The Grotto. We calculate the swell size based on the mean wave height (trough to crest) of each third highest wave. For more information on surf forecasts for the next ten days, please visit sea state forecast The Grotto. Data in table shown for 5 September 2025, time in GMT 0 format (you can change the time zone on the sea state forecast page)
0-3 h | 3-6 h | 6-9 h | 9-12 h |
---|---|---|---|
1' 11" | 1' 10" | 2' 4" | 3' 2" |
0.59 m | 0.56 m | 0.71 m | 0.97 m |
12-15 h | 15-18 h | 18-21 h | 21-24 h |
---|---|---|---|
4' 7" | 6' 2" | 6' 11" | 5' 8" |
1.4 m | 1.89 m | 2.11 m | 1.72 m |
Data in a table show The Grotto temperature today (5 September 2025). For more information and forecast for a few days, go to the weather forecast The Grotto.
0-3 h | 3-6 h | 6-9 h | 9-12 h |
---|---|---|---|
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16.2°C | 16.3°C | 16.5°C | 16.4°C |
12-15 h | 15-18 h | 18-21 h | 21-24 h |
---|---|---|---|
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17.1°C | 16.4°C | 16.3°C | 15.5°C |
You may also be interested in other sections of our site for The Grotto: Sunrise and Sunset, Tides
These figures shows the average, minimum and maximum monthly water temperature in The Grotto. In addition to the table values, the graph below displays of changes average surface temperature during the year. Values are calculated based on the data over the past 10 years. Using them, you can check the water temperature in The Grotto on any day of this period that interests you. Click on the month link and you will see a table for each day, or alternatively you can view the temperature curve of the month and select 2 different years you want to compare, either in a table or as a curve
Month | Avr | Min | Max | |
---|---|---|---|---|
January | 3°C | -0.3°C | 5.1°C | cold |
Water temperature in The Grotto in January | ||||
February | 1°C | -1°C | 3.3°C | cold |
Water temperature in The Grotto in February | ||||
March | 0.9°C | -0.9°C | 3.3°C | cold |
Water temperature in The Grotto in March | ||||
April | 1.7°C | -0.3°C | 4.5°C | cold |
Water temperature in The Grotto in April | ||||
May | 4°C | 1.1°C | 9.3°C | cold |
Water temperature in The Grotto in May | ||||
June | 9.2°C | 2.9°C | 17.1°C | cold |
Water temperature in The Grotto in June | ||||
July | 17.4°C | 8.8°C | 21.8°C | cold |
Water temperature in The Grotto in July | ||||
August | 19.7°C | 16°C | 23°C | cold |
Water temperature in The Grotto in August | ||||
September | 18°C | 14.3°C | 21.1°C | cold |
Water temperature in The Grotto in September | ||||
October | 13.5°C | 9.5°C | 18.1°C | cold |
Water temperature in The Grotto in October | ||||
November | 8.7°C | 5.3°C | 12.7°C | cold |
Water temperature in The Grotto in November | ||||
December | 5.5°C | 2.3°C | 8°C | cold |
Water temperature in The Grotto in December |