St. John's in September
In September, St. John's averages 17°C (62°F) during the day and 11°C (52°F) at night, with frequent rain — about 18 days of the month see precipitation (116 mm total).
ShoulderConditions are cool — bring a jacket for evenings. Expect daily rain or showers, often in heavy bursts.
September is one of the wetter and less comfortable months in St. John's. If your dates are flexible, consider a different time of year.
How September compares to the rest of the year in St. John's
September is one of the warmest months in St. John's (3rd of 12) and moderately rainy compared to the rest of the year (9th of 12). Daytime temperature runs 8°C above the annual average (9°C). September runs 3°C cooler than August (20°C) and cools 5°C in October (12°C).
September sunrise & sunset in St. John's
Times shown for St. John's local time (America/St_Johns), calculated for the 15th of September. They shift by a few minutes day to day across the month.
Photography light in St. John's — September
Golden-hour and blue-hour windows for the 15th of September, in St. John's's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — St. John's in September
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on September's tier (Shoulder) and St. John's's popularity.
Crowds & pricing — September in St. John's
St. John's is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.
Sun & mosquito risk — September in St. John's
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
St. John's in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | 1°C / 34°F | -5°C / 23°F | 160 mm | 22 | — |
| February | 0°C / 32°F | -6°C / 20°F | 123 mm | 19 | — |
| March | 1°C / 34°F | -4°C / 24°F | 120 mm | 20 | — |
| April | 5°C / 41°F | -1°C / 31°F | 112 mm | 19 | — |
| May | 9°C / 49°F | 3°C / 37°F | 91 mm | 17 | — |
| June | 14°C / 58°F | 8°C / 46°F | 98 mm | 18 | — |
| July | 19°C / 66°F | 13°C / 55°F | 80 mm | 17 | — |
| August | 20°C / 68°F | 14°C / 58°F | 94 mm | 18 | — |
| September | 17°C / 62°F | 11°C / 52°F | 116 mm | 18 | — |
| October | 12°C / 53°F | 7°C / 44°F | 102 mm | 18 | — |
| November | 7°C / 45°F | 2°C / 35°F | 133 mm | 20 | — |
| December | 3°C / 37°F | -2°C / 28°F | 124 mm | 19 | — |
Other cities with similar September weather
🌍 See the full ranked list of climate twins for St. John's in September →
Frequently asked questions
How hot is St. John's in September?
In September, St. John's averages a high of 17°C (62°F) and a low of 11°C (52°F) — generally mild and pleasant.
Does it rain a lot in St. John's in September?
September is quite rainy in St. John's, with about 18 rainy days on average.
Is September a good time to visit St. John's?
September is mild and pleasant but on the rainy side. It suits travelers who are comfortable with mild and pleasant weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for St. John's in September?
Pack a warm jacket and layers, plus a compact umbrella or rain jacket. See the full September packing list for St. John's for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.