World Resorts Canada Saint John Weather

Saint John weather in September

Weather in Saint John: September

Average day temperature: 66.3°F
Average night temperature: 53.8°F
Sea water temperature: 58.4°F
Number of sunny days: 10 days
Day length: 11.7 - 13.3 hours
Number of rainy days: 2 days
Precipitation totals: 1.0 in.

Air temperature in September, °F

Show year:
2025
2024
2023

The highest day temperature during September of 2025 was 77°F. At the same time the lowest night temperature was 40°F. Daily and nightly averages during September were 65.9°F and 51.5°F.

Sea water temperature in Saint John in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 58.5°F. The highest and lowest sea temperatures during the month were 61.2°F and 56.7°F.

Sunny, partly cloudy and cloudy days

Number of sunny, partly cloudy and cloudy days in September is almost equal.

Precipitation total in September, in.

Precipitation total value in Saint John in September is 1.0 in. Other months of the year show relatively similar values.

Wind speed in September, mph

The average wind speed value in September is 6.6 mph It makes September one of the least windy months of the year.

Average sunny hours

This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 6.3.

Best time for vacation in Saint John

Sunniest months:
September 10 days
October 10 days
August 9 days
Warmest months:
July 72.6 °F
August 71.8 °F
June 68.1 °F
Warmest sea temp:
August 59.6 °F
September 58.4 °F
July 56.9 °F
Coldest months:
January 25.6 °F
February 25.9 °F
December 32.5 °F
Rainiest months:
October 3 days
July 3 days
June 2 days
Windiest months:
December 9.0 mph
March 8.8 mph
February 8.6 mph

Saint John on a weather map

Saint John
+18°F
E 16 mph
Feels like: +3°F
Precip.: 0%
Places in Canada:
Name
°F
+45°F
+46°F
+16°F
+30°F
-13°F
+14°F
+12°F
+9°F
+25°F
+7°F
+18°F
+37°F
+37°F
+21°F
24 Hours Forecast
Saint John
Local time: 16:37
December 30, tuesday
1800
18°F
E
16 mph
2100
16°F
E
15 mph
December 31, wednesday
0000
14°F
E
15 mph
0300
12°F
E
16 mph
0600
10°F
E
14 mph
0900
14°F
E
12 mph
1200
19°F
E
13 mph
1500
23°F
E
9 mph
Units of measurement: °C / °F