September weather forecast
Guernsey

September in Guernsey signals the onset of the autumn season. During this month, the island starts to experience a gradual decline in temperatures, which typically range from 15°C (59°F) to 17°C (62.6°F). Despite this decrease, the weather remains relatively mild and enjoyable for outdoor activities.

Regarding precipitation, September sees an increase compared to the summer months. The island typically receives around 50mm (1.97") of rain, spread over approximately 12 to 15 days. These early autumn showers contribute to a lush landscape, adding to the picturesque beauty of Guernsey during this transitional period.

Compared to August, September presents cooler temperatures and a higher level of rainfall, marking a shift from the summer season. As Guernsey progresses into October, the temperatures continue to fall, and the rainfall levels rise further, fully ushering in the cooler and wetter conditions of the autumn season.

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• Saint Sampson - September »
  In Saint Sampson in September, it is raining for 13.5 days, with typically 31mm (1.22") of accumulated precipitation. On the first day of September in Saint Sampson, sunrise is at 06:25 and sunset at 19:54.
• Guernsey - September »
  In Guernsey, during September, the rain falls for 13.5 days and regularly aggregates up to 31mm (1.22") of precipitation. On the last day of September, in Guernsey, sunrise is at 07:08 and sunset at 18:52 BST.
• Saint Peter Port - September »
  In Saint Peter Port, Guernsey, during September, the rain falls for 13.5 days and regularly aggregates up to 31mm (1.22") of precipitation. As Saint Peter Port welcomes September, the average high-temperature is noted at a still refreshing 17.2°C (63°F), closely aligning with the preceding month.
• Alderney - September »
  September is the month with the warmest seawater in Alderney, with an average sea temperature of 17.4°C (63.3°F). On the first day of September in Alderney sunrise is at 06:24 and sunset at 19:53.
• Braye du Valle - September »
  In Braye du Valle in September, it is raining for 13.5 days, with typically 31mm (1.22") of accumulated precipitation. September's arrival in Braye du Valle shows an average high-temperature of a still comfortable 17.2°C (63°F), hardly different from the previous month.
• Fort George - September »
  The onset of September in Fort George notes an average high-temperature of a still enjoyable 17.2°C (63°F), subtly shifted from August's 17.8°C (64°F). September spells the onset of autumn in Fort George with temperatures slowly starting to cool down.
• Saint Andrew - September »
  In Saint Andrew, in September, it is raining for 13.5 days, with typically 31mm (1.22") of accumulated precipitation. How many hours of sunshine does Saint Andrew have in September?