September weather forecastGrethem, Germany
September
Weather in September
September, the first month of the autumn in Grethem, is still a refreshing month, with an average temperature ranging between min 11.1°C (52°F) and max 19.4°C (66.9°F).Temperature
With the beginning of September, the average high-temperature shows a small decrease, transitioning from a warm 23.9°C (75°F) in August to a refreshing 19.4°C (66.9°F). Grethem's nights in September cool down to an average low-temperature of 11.1°C (52°F).Humidity
In September, the average relative humidity is 76%.Rainfall
In Grethem, in September, during 10.7 rainfall days, 20mm (0.79") of precipitation is typically accumulated. In Grethem, during the entire year, the rain falls for 149.4 days and collects up to 335mm (13.19") of precipitation.Snowfall
May through October are months without snowfall.Daylight
In September, the average length of the day in Grethem, Germany, is 12h and 40min.On the first day of September, sunrise is at 06:33 and sunset at 20:09. On the last day of the month, sunrise is at 07:22 and sunset at 19:00 CEST.
Sunshine
The average sunshine in September in Grethem is 8h.UV index
In September, the average daily maximum UV index in Grethem is 4. A UV Index value of 3 to 5 symbolizes a medium health hazard from unprotected exposure to Sun's UV rays for the ordinary person.Note: In September, the maximum UV index of 4 transforms into these recommendations:
Be cautious. Those with fair skin can be subjected to burns in fewer than 30 minutes. To guard against the harmful effects of the Sun, minimize exposure during midday. Combat UV radiation's detrimental effects with sun-safe clothing and UV-blocking eyewear.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Grethem, Germany
- Average high temperature in September: 19.4°C
The warmest month (with the highest average high temperature) is August (23.9°C).
The month with the lowest average high temperature is January (3.1°C).
- Average low temperature in September: 11.1°C
The month with the highest average low temperature is August (14.2°C).
The coldest month (with the lowest average low temperature) is January (-0.7°C).
Average pressure in September
Grethem, Germany
- Average pressure in September: 1017.1mbar
The month with the highest atmospheric pressure is September (1017.1mbar).
The month with the lowest atmospheric pressure is November (1012.7mbar).
Average wind speed in September
Grethem, Germany
- Average wind speed in September: 12.8km/h
The windiest month (with the highest average wind speed) is December (17.2km/h).
The calmest month (with the lowest average wind speed) is August (12.5km/h).
Average humidity in September
Grethem, Germany
- Average humidity in September: 76%
The months with the highest relative humidity are January and December (88%).
The month with the lowest relative humidity is August (70%).
Average rainfall in September
Grethem, Germany
- Average rainfall in September: 20mm
The wettest month (with the highest rainfall) is July (39mm).
The driest month (with the least rainfall) is April (16mm).
Average rainfall days in September
Grethem, Germany
- Average rainfall days in September: 10.7 days
The month with the highest number of rainy days is July (15.7 days).
The month with the least rainy days is February (10 days).
Average snowfall in September
Grethem, Germany
- Average snowfall in September: 0mm
The month with the highest snowfall is December (43mm).
The months with the least snowfall are May, June, July, August, September and October (0mm).
Average snowfall days in September
Grethem, Germany
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (5.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight in September /
Average sunshine in September
Grethem, Germany
- Average daylight in September: 12h and 42min
The month with the longest days is June (Average daylight: 16h and 48min).
The month with the shortest days is December (Average daylight: 7h and 42min).
- Average sunshine in September: 8h and 0min
The month with the most sunshine is August (Average sunshine: 9h and 30min).
The month with the least sunshine is December (Average sunshine: 3h and 12min).
Average sunshine days in September
Grethem, Germany
- Average sunshine days in September: 16.8 days
The months with the most sunshine days are August and September (16.8 days).
The month with the least sunshine days is July (12.5 days).
Average UV index in September
Grethem, Germany
- Average UV index in September: 4
The months with the highest UV index are June, July and August (UV index 5).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover in September
Grethem, Germany
- Average cloud cover in September: 44
The month with the most cloud cover is December (Cloud cover 68).
The month with the least cloud cover is August (Cloud cover 38).
Average visibility in September
Grethem, Germany
- Average visibility in September: 9km
The months with the highest visibility are February, March, April, May, June, July, August, September, October, November and December (9km).
The month with the lowest visibility is January (8km).
