Measurements:
°C
°F
Saint John
54°F
W 14 mph
Feels like: 50°F
Precip: 47%
World Resorts Canada Saint John Weather

Saint John Sea Water Temperature

Current Sea Water Temperature:
+56.8°F
Maximum Sea Water Temperature in September: 64.0°F
Minimum Sea Water Temperature in September: 55.6°F
Average water temperature in September: 59.1°F

Sea Water Temperature for the Last 10 Days:

September 28 56.8°F September 23 57.2°F
September 27 57.8°F September 22 57.6°F
September 26 57.8°F September 21 56.6°F
September 25 58.2°F September 20 57.4°F
September 24 57.8°F September 19 57.2°F

When is the Warmest Sea for Saint John?

According to our data for the last three years for Saint John the highest average sea water temperature was in August, September and July.

Average Water Temperature by Month, °F

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for Saint John was 59.4°F. The maximum and minimum values were 52.8°F and 63.2°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for Saint John was 58.1°F. The maximum and minimum values were 56.6°F and 60.0°F respectively.

Sea Water Temperature in July

Select Year: 2026 2025 2024

The average sea surface temperature in July 2026 for Saint John was 55.0°F. The maximum and minimum values were 50.8°F and 62.0°F respectively.

Best Time to Visit Saint John
The most sunny months:
September 10 days
October 10 days
August 9 days
The most warm months:
July 74.9 °F
August 73.8 °F
June 69.6 °F
Warmest sea temperature:
August 60.4 °F
September 59.1 °F
July 57.3 °F
The most cold months:
January 22.9 °F
February 23.7 °F
December 30.5 °F
The most rainy months:
August 3 days
October 3 days
July 3 days
The most windy months:
March 9 mph
December 9 mph
February 8 mph

Saint John on the Weather Map

Canada Resorts:
NAME
F°
Halifax +56
Moncton +54
Montreal +52
Nanaimo +58
Niagara Falls +64
Ottawa +54
Prince Edward Island +56
Quebec +50
Saint Andrews +56
St. John's +42
Sydney +54
Toronto +72
Vancouver +58
Victoria +58
Winnipeg +52
24 Hours Weather Forecast
Saint John
Local time: 18:58
28 sep, monday
2100 56°F
W
12 mph
29 sep, tuesday
0000 56°F
W
11 mph
0300 56°F
W
9 mph
0600 58°F
W
9 mph
0900 58°F
SW
9 mph
1200 60°F
SW
7 mph
1500 60°F
SW
6 mph
1800 58°F
S
8 mph