Contents
- Weather in September
- Frequently asked questions
- Average temperature in September
- Average pressure in September
- Average wind speed in September
- Average humidity in September
- Average rainfall in September
- Average rainfall days in September
- Average snowfall in September
- Average snowfall days in September
- Average daylight in September
- Average sunshine in September
- Average sunshine days in September
- Average UV index in September
- Average cloud cover in September
- Average visibility in September
Weather in September
Temperature
In September, Holywood's weather conditions record an average high-temperature of a mild 14.8°C (58.6°F), demonstrating little divergence from the preceding month. During the month of September, Holywood identifies an average nighttime low-temperature of 10.1°C (50.2°F), slightly lower than its daytime counterpart.Humidity
The average relative humidity in September is 87%.Rainfall
In Holywood, during September, the rain falls for 16.4 days and regularly aggregates up to 40mm (1.57") of precipitation. Throughout the year, there are 220.2 rainfall days, and 626mm (24.65") of precipitation is accumulated.Snowfall
April through October are months without snowfall in Holywood.Daylight
The average length of the day in September in Holywood is 12h and 43min.On the first day of September in Holywood, United Kingdom, sunrise is at 6:31 am and sunset at 8:14 pm. On the last day of the month, sunrise is at 7:24 am and sunset at 7:01 pm BST.
Sunshine
In Holywood, the average sunshine in September is 6h.UV index
The average daily maximum UV index in September is 3. A UV Index of 3 to 5 symbolizes a medium health hazard from exposure to the Sun's UV rays for the average person.Note: A daily high UV index of 3 in September leads to these guidelines:
Exercise prevention - Warding off sunburn is urged. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. It's wise to wear UVA and UVB-blocking sunglasses when the sun shines brightly.
Frequently asked questions
What is the temperature in September in Holywood?
What is the average humidity in September in Holywood?
How much does it rain in Holywood in September?
When it does not snow in Holywood?
What is the average length of the day in September in Holywood?
When are sunrise and sunset in September in Holywood?
How many hours of sunshine does Holywood have in September?
How high is the UV index in September in Holywood?
Average temperature in September
Holywood, United Kingdom
- Average high temperature in September: 14.8°C
The warmest month (with the highest average high temperature) is July (16.9°C).
The month with the lowest average high temperature is January (6.8°C).
- Average low temperature in September: 10.1°C
The month with the highest average low temperature is August (11.3°C).
The coldest month (with the lowest average low temperature) is February (2.8°C).
Average pressure in September
Holywood, United Kingdom
- Average pressure in September: 1014.2mbar
The month with the highest atmospheric pressure is May (1015.6mbar).
The month with the lowest atmospheric pressure is November (1007.3mbar).
Average wind speed in September
Holywood, United Kingdom
- Average wind speed in September: 17km/h
The windiest month (with the highest average wind speed) is January (21.3km/h).
The calmest months (with the lowest average wind speed) are June and July (13.7km/h).
Average humidity in September
Holywood, United Kingdom
- Average humidity in September: 87%
The months with the highest relative humidity are January and December (88%).
The months with the lowest relative humidity are April and May (83%).
Average rainfall in September
Holywood, United Kingdom
- Average rainfall in September: 40mm
The wettest month (with the highest rainfall) is August (72mm).
The driest month (with the least rainfall) is May (38mm).
Average rainfall days in September
Holywood, United Kingdom
- Average rainfall days in September: 16.4 days
The month with the highest number of rainy days is August (23 days).
The month with the least rainy days is April (16.1 days).
Average snowfall in September
Holywood, United Kingdom
- Average snowfall in September: 0mm
The month with the highest snowfall is February (25mm).
The months with the least snowfall are April, May, June, July, August, September and October (0mm).
Average snowfall days in September
Holywood, United Kingdom
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is February (2.8 days).
The months with the least snowfall days are April, May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Holywood, United Kingdom
- Average daylight in September: 12h and 4min
The month with the longest days is June (Average daylight: 17h and 12min).
The month with the shortest days is December (Average daylight: 7h and 24min).
- Average sunshine in September: 6h and 0min
The month with the most sunshine is June (Average sunshine: 7h and 18min).
The month with the least sunshine is February (Average sunshine: 3h and 30min).
Average sunshine days in September
Holywood, United Kingdom
- Average sunshine days in September: 8.4 days
The month with the most sunshine days is April (11.5 days).
The month with the least sunshine days is August (5.6 days).
Average UV index in September
Holywood, United Kingdom
- Average UV index in September: 3
The months with the highest UV index are May, June, July and August (UV index 4).
The months with the lowest UV index are January, February, March, November and December (UV index 2).
Average cloud cover in September
Holywood, United Kingdom
- Average cloud cover in September: 58
The months with the most cloud cover are January and February (Cloud cover 63).
The month with the least cloud cover is April (Cloud cover 55).
Average visibility in September
Holywood, United Kingdom
- Average visibility in September: 9km
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (9km).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (9km).
Holywood, United Kingdom
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