Weather in Guernsey for September 2025
In general, the average temperature in Guernsey at the beginning of September is 18.9 °C. As the month progressed, temperatures tended to moderately fall, reaching an average of 17.1 °C by the end of September.
The climate of Guernsey in September is notably wet, with an average of 15 rainy days.
Is September a good time to visit Guernsey? check out the best time to travel to Guernsey page.
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Guernsey in September average weather
| Mon. | Tue. | Wed. | Thu. | Fri. | Sat. | Sun. |
|---|---|---|---|---|---|---|
| 1  18° | 2  19° | 3  19° | 4 19° | 5 19° | 6 19° | 7 19° |
| 8 19° | 9 19° | 10 19° | 11 17° | 12  16° | 13  16° | 14 17° |
| 15 18° | 16 18° | 17 18° | 18 18° | 19 18° | 20 18° | 21 17° |
| 22  16° | 23 17° | 24 17° | 25 17° | 26 18° | 27 17° | 28 17° |
| 29 17° | 30 17° |
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Temperatures trend during September in Guernsey
September weather day by day
| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| 1 Sept. | Light rain shower | 18° /16° | 9.2 mm | 4 | |
| 2 Sept. | Partly cloudy | 19° /16° | 0.6 mm | 5 | |
| 3 Sept. | Sunny | 19° /16° | 0.3 mm | 5 | |
| 4 Sept. | Sunny | 19° /16° | 0.4 mm | 5 | |
| 5 Sept. | Sunny | 19° /16° | 0.9 mm | 5 | |
| 6 Sept. | Patchy rain possible | 19° /17° | 0.9 mm | 5 | |
| 7 Sept. | Patchy rain possible | 19° /17° | 7.3 mm | 5 | |
| 8 Sept. | Partly cloudy | 19° /16° | 5.1 mm | 5 | |
| 9 Sept. | Patchy rain possible | 19° /16° | 0.7 mm | 5 | |
| 10 Sept. | Patchy rain possible | 19° /16° | 2.7 mm | 5 | |
| 11 Sept. | Partly cloudy | 17° /15° | 1 mm | 5 | |
| 12 Sept. | Cloudy | 16° /15° | 1.2 mm | 4 | |
| 13 Sept. | Overcast | 16° /14° | 0.1 mm | 4 | |
| 14 Sept. | Partly cloudy | 17° /14° | 0 mm | 5 | |
| 15 Sept. | Sunny | 18° /16° | 0 mm | 6 | |
| 16 Sept. | Patchy rain possible | 18° /16° | 0.8 mm | 4 | |
| 17 Sept. | Light rain shower | 18° /16° | 3.1 mm | 4 | |
| 18 Sept. | Light rain shower | 18° /16° | 0.9 mm | 4 | |
| 19 Sept. | Patchy rain possible | 18° /16° | 0.6 mm | 5 | |
| 20 Sept. | Light rain shower | 18° /16° | 15.1 mm | 4 | |
| 21 Sept. | Light rain shower | 17° /15° | 5.1 mm | 4 | |
| 22 Sept. | Patchy light drizzle | 16° /15° | 1.7 mm | 4 | |
| 23 Sept. | Patchy rain possible | 17° /14° | 5.7 mm | 4 | |
| 24 Sept. | Sunny | 17° /15° | 1.2 mm | 5 | |
| 25 Sept. | Overcast | 17° /15° | 2 mm | 4 | |
| 26 Sept. | Patchy rain possible | 18° /14° | 4.3 mm | 4 | |
| 27 Sept. | Patchy rain possible | 17° /14° | 4.2 mm | 4 | |
| 28 Sept. | Patchy rain possible | 17° /13° | 0.6 mm | 4 | |
| 29 Sept. | Cloudy | 17° /14° | 1.9 mm | 4 | |
| 30 Sept. | Partly cloudy | 17° /14° | 1.5 mm | 5 | |
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Guide for Guernsey in September
In Guernsey, September typically experiences mild and pleasant weather, making it an ideal time to visit this beautiful island. At the beginning of the month, the weather in Guernsey is generally warm with average temperatures around 18° during the day and 12° at night.
The island enjoys a moderate amount of sunshine, and the sea temperature remains relatively comfortable for swimming and water activities.
As the month progresses, the weather in Guernsey gradually transitions into autumn. By the end of September, temperatures may slightly decrease to around 16° during the day and 11° at night.
While the days remain relatively mild, the evenings become cooler, creating a refreshing atmosphere for outdoor strolls and al fresco dining.
Guernsey in September also experiences occasional rainfall, so it's advisable for visitors to pack a light waterproof jacket or umbrella. However, these showers are typically short-lived and do not significantly impact outdoor activities.
Overall, September offers a delightful blend of warm temperatures, comfortable sea conditions, and picturesque landscapes, making it an excellent time to explore the charming island of Guernsey.
Guernsey in September - FAQ
What to pack to Guernsey in September?
As you prepare for your trip to Guernsey in September, it's important to consider the typical weather patterns for the time of year. Below is a carefully tailored packing list to ensure that your time in Guernsey, during September, is comfortable and enjoyable, regardless of the weather conditions.
- Clothing
- Layered Clothing: Light sweaters, long-sleeve shirts, light jackets, and comfortable pants
- Rain Gear: Lightweight, waterproof clothing
- Footwear
- Waterproof Shoes
- Accessories
- Umbrellas/Raincoats: For rainy days
September rainfall patterns in Guernsey
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