Saint John (NB) Weather & Climate: Best Time to Visit
Average temperatures, rainfall, sunshine and the best time to visit Saint John.
Climate overview of Saint John
Saint John, New Brunswick, Canada, experiences significant temperature variation throughout the year. Summers bring daytime highs of 21°C (70°F) in August, while winters cool to -1°C (30°F) in January.
Rain/snowfall is high, totalling around 1384 mm (54 in) per year. December is the wettest month and August the driest. The city also experiences pleasant summers and very cold winters.
Saint John Weather by Month
Pick a month to see the average temperature, rainfall and sunshine in Saint John - and find the best time to visit.
Monthly Temperature in Saint John
Depending on the time of the year, temperatures range from pleasant to very cold in Saint John. Average maximum daytime temperatures range from a pleasant 21°C (70°F) in August, the warmest time of the year, to a very cold -1°C (30°F) during cooler months like January.
At night, you can expect temperatures ranging from 14°C (57°F) in August to around -10°C (14°F) during January.
Check out our detailed temperature page for more information.
Temperature ranges by month
Rainfall in Saint John
Saint John has a relatively rain/snowy climate with high precipitation levels, averaging 1384 mm (54 in) of rain/snowfall annually. Year-round, Saint John has a balanced climate with minimal variation in precipitation. The difference between the wettest month, December, with 140 mm (5.5 in), and the driest month, August, with 87 mm (3.4 in), is minimal. For more details, please visit our Saint John Precipitation page.
The mean monthly precipitation over the year, including rain, hail, and snow
The average number of days each month with precipitation
Best Time to Visit Saint John
Monthly ratings reflect general weather comfort, based on daytime temperature and rainfall. Swimming and winter conditions are highlighted separately where relevant.
- Best overall: July and August
- Warmest weather: July and August
- Seasonal pattern: Pleasant summers and very cold winters
- Coldest conditions: January, with freezing nights around -10°C (14°F).
Frequently asked questions about the climate in Saint John
What is the best time to visit Saint John?
July and August typically offer the most optimal weather in Saint John. In contrast, January, February, March, April, May, October, November and December tend to have less optimal conditions. Saint John has pleasant summers and very cold winters.
What temperatures can I expect in Saint John?
Daytime highs range from -1°C (30°F) in January to 21°C (70°F) in August. Nighttime lows range from -10°C (14°F) to 14°C (57°F). Temperatures vary considerably through the year.
How much rain does Saint John get?
Annual rainfall is around 1384 mm (54 in). December is the wettest month with 140 mm (5.5 in), while August is the driest with 87 mm (3.4 in). In the coldest months, precipitation may fall as snow/rain.
Saint John 3-Day Forecast
Saint John on the map
Saint John is highlighted - select any city to see its climate.
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