Guernsey Weather in September
Guernsey in September averages 18°C (64°F) during the day and 16°C (61°F) at night. Keep in mind that quite a bit of rainfall is expected this month.
Rainfall in Guernsey in September
Historically, approximately 13 days this month are expected to have rain, averaging 66 mm (2.6 in). The rainfall pattern this month is fairly balanced. Showers tend to be moderate rather than extreme.
Temperature in Guernsey in September
Daytime highs in Guernsey in September reach 18°C (64°F), with nights around 16°C (61°F). Temperatures can feel cooler in the morning and evening, so layering is often the best approach. At 16°C (61°F) overnight, it can feel quite a bit cooler after dark. Worth packing something warmer for evenings, but the cooler temperatures are ideal for sleeping.
Sunshine in Guernsey in September
With about 182 hours of sunshine, the area enjoys a nice balance of sun and overcast, creating a pleasant environment.If you favor pleasant temperatures and minimal rainfall, September is one of the best months to visit Guernsey.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United Kingdom, check out our Guernsey's climate page.
Guernsey Temperature in September
Min Temperature
16°C (61°F)
Max Temperature
18°C (64°F)
Chance of Rain
43%
Precipitation
66 mm (2.6 in)
Rainy days
13 days
Sunshine
182 hours
Percentage Sunshine
47%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Guernsey typically stay consistent throughout September, with daily highs averaging around 18°C (64°F). Nights are cool, with lows around 13°C (55°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Guernsey in September
Browse day-by-day weather records for Guernsey spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Guernsey historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Guernsey.
- The warmest day in September was on September 9, 2023, with a maximum of 30°C (86°F).
- The lowest daytime temperature in September was 11°C (52°F), recorded on September 16, 1986.
- Nighttime temperatures dropped to 8°C (46°F) on September 23, 1986, marking the coldest September night on record.
Best Places in the United Kingdom in September
Find out more about the weather in the United Kingdom and which places have the best travel conditions in this month. See all of the United Kingdom in September →
perfect weather
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tolerable
unpleasant
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What to Wear in Guernsey in September
Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Wet weather is likely, so pack waterproof gear for multiple rainy days. Sunglasses could come in handy during the sunnier parts of your trip.What To Do in Guernsey in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United Kingdom, check out our Guernsey's climate page.
See the full Guernsey climate overview or explore weather in the United Kingdom.
