September Weather in Saint Andrew, Guernsey

Last updated: August 23, 2025

In September, the average temperature in Saint Andrew, Guernsey is a comfortable 17°C (62°F), with lows dipping to 12°C (54°F) and highs reaching up to 21°C (71°F). Expect around 63 mm (2.5 in) of precipitation over approximately 9 days, and a pleasant average humidity of 76%.

September Temperature in Saint Andrew

In September in Saint Andrew, the average temperature is 17°C (62°F). Maximums can reach 21°C (71°F), and minimums can be as low as 12°C (54°F). This mild climate makes Saint Andrew an ideal destination for travelers looking to enjoy comfortable weather.

September Weather in Saint Andrew: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Saint Andrew, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Saint Andrew, September typically has an average temperature of 17°C (62°F), with highs reaching up to 21°C (71°F) and lows dropping to around 12°C (54°F).

Data source: Temperature data for Saint Andrew generated using information from the Copernicus Climate Change Service.

September Precipitation in Saint Andrew

In Saint Andrew in September, the total precipitation amount is 63 mm (2.5 in) spread over a duration of 9 days.

September Precipitation Trends in Saint Andrew

The chart displays monthly precipitation patterns in Saint Andrew, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Saint Andrew, September typically receives around 63 mm (2.5 inches) of precipitation spread over approximately 9 days.

Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

September Humidity in Saint Andrew

In Saint Andrew in September, humidity is 76%. With an average temperature of 17°C (62°F), this humidity feels like a warm, enveloping embrace, making travel feel slightly more challenging as it can lead to a sticky discomfort, especially during outdoor excursions.

September Average Humidity in Saint Andrew

This chart illustrates the average monthly humidity levels in Saint Andrew, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Saint Andrew is approximately 76%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Saint Andrew

In Saint Andrew in September, the maximum UV index is 6, which corresponds to a high Exposure Category. The time to burn is approximately 25 minutes. To find the hourly UV index in Saint Andrew, you can refer to this Hourly UV Index in Saint Andrew.

Maximum UV Index Levels in Saint Andrew for September

The chart shows the monthly maximum UV Index (UVI) for Saint Andrew in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Saint Andrew typically reaches 6, which falls under the high exposure category.

Data source: Saint Andrew September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How September Weather in Saint Andrew Compares to Other Months

Weather in Saint Andrew varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Saint Andrew, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Saint Andrew, showing how September’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	9°C (49°F)	94 mm (3.7 inches)	89%	low
February Weather	9°C (48°F)	86 mm (3.4 inches)	88%	moderate
March Weather	9°C (49°F)	73 mm (2.9 inches)	85%	moderate
April Weather	10°C (50°F)	34 mm (1.3 inches)	84%	high
May Weather	12°C (54°F)	55 mm (2.2 inches)	81%	high
June Weather	14°C (58°F)	59 mm (2.3 inches)	77%	very high
July Weather	16°C (62°F)	37 mm (1.5 inches)	63%	very high
August Weather	17°C (63°F)	50 mm (2.0 inches)	71%	high
September Weather	17°C (62°F)	63 mm (2.5 inches)	76%	high
October Weather	15°C (59°F)	144 mm (5.7 inches)	89%	moderate
November Weather	12°C (54°F)	126 mm (5.0 inches)	90%	low
December Weather	11°C (51°F)	163 mm (6.4 inches)	90%	low