Measurements:
°C
°F
Saint John
40°F
N 23 mph
Feels like: 28°F
Precip: 100%
World Resorts Canada Saint John Weather

Saint John Sea Water Temperature

Current Sea Water Temperature:
+39.4°F
Maximum Sea Water Temperature in January: 45.4°F
Minimum Sea Water Temperature in January: 35.8°F
Average water temperature in January: 40.3°F

Sea Water Temperature for the Last 10 Days:

January 09 39.4°F January 04 40.2°F
January 08 39.0°F January 03 40.4°F
January 07 39.2°F January 02 40.8°F
January 06 39.6°F January 01 40.8°F
January 05 40.0°F December 31 41.0°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: 2025 2024 2023

The average sea surface temperature in August 2025 for Saint John was 60.5°F. The maximum and minimum values were 58.0°F and 63.0°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for Saint John was 59.4°F. The maximum and minimum values were 57.4°F and 62.4°F respectively.

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for Saint John was 56.1°F. The maximum and minimum values were 49.8°F and 64.6°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 75.1 °F
August 74.3 °F
June 70.1 °F
Warmest sea temperature:
August 60.6 °F
September 59.3 °F
July 57.7 °F
The most cold months:
January 22.9 °F
February 23.2 °F
December 30.5 °F
The most rainy months:
October 3 days
July 3 days
June 2 days
The most windy months:
December 9 mph
March 9 mph
February 8 mph

Saint John on the Weather Map

Canada Resorts:
NAME
Halifax +34
Kingston +36
Montreal +44
Niagara Falls +40
Ottawa +38
Prince Edward Island +30
Quebec +30
Saint John +40
St. John's +24
Sydney +30
Toronto +36
Vancouver +48
Victoria +46
Winnipeg +8
Yellowknife -32
24 Hours Weather Forecast
Saint John
Local time: 22:35
10 jan, saturday
0000 40°F
N
23 mph
0300 42°F
NE
24 mph
0600 36°F
E
20 mph
0900 38°F
SE
18 mph
1200 38°F
E
11 mph
1500 38°F
SE
10 mph
1800 36°F
SE
5 mph
2100 32°F
SE
2 mph