Monthly climate guide
Saint Helier weather in September
September in Saint Helier is typically mild, with average daytime highs around 19°C (66°F) and night-time lows near 15°C (59°F). The month usually brings about 52 mm of rain (some rain) and is often cloudy. Daytime highs are about the same as August and 3°C warmer than October.
What stands out in September
- Days and nights are close, only about 4°C apart.
- September is Saint Helier's third warmest month.
- September brings early autumn to Saint Helier.
Avg high
19°C
66°F
Avg low
15°C
59°F
Rainfall
52 mm
some rain
Humidity
81%
relative
Sky
69%
cloud · often cloudy
Saint Helier weather by month
Show the monthly averages as a table
| Month | Avg high | Avg low | Rain | Humidity | Cloud cover |
|---|---|---|---|---|---|
| January | 9°C / 48°F | 6°C / 43°F | 89 mm | 86% | 87% |
| February | 9°C / 48°F | 6°C / 42°F | 74 mm | 85% | 83% |
| March | 10°C / 50°F | 7°C / 44°F | 59 mm | 85% | 78% |
| April | 13°C / 55°F | 8°C / 47°F | 48 mm | 82% | 69% |
| May | 15°C / 59°F | 11°C / 51°F | 50 mm | 83% | 68% |
| June | 18°C / 64°F | 14°C / 56°F | 57 mm | 83% | 69% |
| July | 20°C / 67°F | 16°C / 60°F | 47 mm | 82% | 61% |
| August | 20°C / 68°F | 16°C / 61°F | 61 mm | 81% | 68% |
| September | 19°C / 66°F | 15°C / 59°F | 52 mm | 81% | 69% |
| October | 16°C / 61°F | 13°C / 55°F | 85 mm | 83% | 80% |
| November | 13°C / 55°F | 10°C / 50°F | 95 mm | 85% | 86% |
| December | 11°C / 51°F | 8°C / 46°F | 111 mm | 86% | 88% |
What to pack for September
- A warm sweater or fleece for layering
- A mid-weight jacket
- A small travel umbrella, just in case
Is September a good time to visit Saint Helier?
Compare the months in the chart above to find your ideal window.
Best time to visit Saint Helier →Cite or embed this data
Writing about this destination? Copy a ready-made citation or embed a live widget — free, just keep the link.
Saint Helier weather in September. WeatherCompare, 2026 (NASA POWER / ERA5, 2011–2020 monthly averages). https://weathercompare.eu/weather/jersey/saint-helier/september
<a href="https://weathercompare.eu/weather/jersey/saint-helier/september">Saint Helier weather in September</a> (WeatherCompare)
<iframe src="https://weathercompare.eu/embed/jersey/saint-helier" width="300" height="160" style="border:0;border-radius:12px" loading="lazy" title="Saint Helier weather in September"></iframe> <p style="font-size:12px"><a href="https://weathercompare.eu/weather/jersey/saint-helier/september">Saint Helier weather in September</a> – WeatherCompare</p>
Saint Helier in September: quick answers
Is September a good time to visit Saint Helier?
Yes. September is one of the best months for Saint Helier, with highs around 19°C and about 52 mm of rain.
How warm is Saint Helier in September?
Average highs are about 19°C (66°F) and average lows about 15°C (59°F), based on 10 years of daily data.
Does it rain a lot in Saint Helier in September?
Saint Helier typically gets around 52 mm of rain in September — some rain.
Figures are long-term averages for the area around Saint Helier (NASA POWER / ERA5, 2011–2020), not a forecast for a specific year. For upcoming days, see the live multi-source forecast.