September weather forecastSlemmestad, Norway
September
Weather in September
The first month of the autumn, September, is still a refreshing month in Slemmestad, Norway, with an average temperature fluctuating between 7.2°C (45°F) and 14.7°C (58.5°F).Temperature
The shift from August to September coincides with a small decrease in the average high-temperature, down to a moderate 14.7°C (58.5°F) from a comfortable 18.9°C (66°F). In the month of September, the nighttime temperature in Slemmestad dips to a steady average of 7.2°C (45°F).Humidity
In Slemmestad, Norway, the average relative humidity in September is 81%.Rainfall
In September, in Slemmestad, Norway, the rain falls for 10.2 days. Throughout September, 27mm (1.06") of precipitation is accumulated. In Slemmestad, during the entire year, the rain falls for 127.7 days and collects up to 307mm (12.09") of precipitation.Snowfall
In Slemmestad, snow does not fall in June through September.Sea temperature
In Slemmestad, in September, the average water temperature is 15.5°C (59.9°F).Note: Swimming becomes less enjoyable for most at a surface water temperature of 15.5°C (59.9°F). As the temperature decreases below 21°C (69.8°F), breathing becomes increasingly difficult.
Daylight
The average length of the day in September in Slemmestad, Norway, is 12h and 51min.On the first day of the month, sunrise is at 06:14 and sunset at 20:20. On the last day of September, in Slemmestad, sunrise is at 07:22 and sunset at 18:53 CEST.
Sunshine
The average sunshine in September is 7.5h.UV index
In September, the average daily maximum UV index is 3. A UV Index of 3 to 5 symbolizes a moderate health risk from unsafe exposure to UV radiation for the ordinary person.Note: In September, the maximum UV index of 3 suggests these recommendations:
Be careful. Light complexion individuals might get burns in fewer than 30 minutes. Solar radiation is at its peak intensity during midday, so it's advisable to stay indoors or in the shade. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Slemmestad, Norway
- Average high temperature in September: 14.7°C
The warmest month (with the highest average high temperature) is July (20.4°C).
The month with the lowest average high temperature is January (-2.4°C).
- Average low temperature in September: 7.2°C
The month with the highest average low temperature is July (10.8°C).
The coldest month (with the lowest average low temperature) is February (-7.8°C).
Average pressure in September
Slemmestad, Norway
- Average pressure in September: 1012.6mbar
The month with the highest atmospheric pressure is April (1014.5mbar).
The month with the lowest atmospheric pressure is December (1008mbar).
Average wind speed in September
Slemmestad, Norway
- Average wind speed in September: 9.5km/h
The windiest month (with the highest average wind speed) is January (9.9km/h).
The calmest month (with the lowest average wind speed) is August (8.3km/h).
Average humidity in September
Slemmestad, Norway
- Average humidity in September: 81%
The month with the highest relative humidity is February (91%).
The month with the lowest relative humidity is May (71%).
Average rainfall in September
Slemmestad, Norway
- Average rainfall in September: 27mm
The wettest month (with the highest rainfall) is July (40mm).
The driest month (with the least rainfall) is April (13mm).
Average rainfall days in September
Slemmestad, Norway
- Average rainfall days in September: 10.2 days
The month with the highest number of rainy days is July (18.3 days).
The month with the least rainy days is February (4.3 days).
Average snowfall in September
Slemmestad, Norway
- Average snowfall in September: 0mm
The month with the highest snowfall is March (73mm).
The months with the least snowfall are June, July, August and September (0mm).
Average snowfall days in September
Slemmestad, Norway
- Average snowfall days in September: 0 days
The month with the highest number of snowfall days is January (10.4 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average sea temperature in September
Slemmestad, Norway
- Average sea temperature in September: 15.5°C
The best month for swimming (with the highest average sea temperature) is August (17.8°C).
The coldest month (with the lowest average sea temperature) is March (3.2°C).
Average daylight in September /
Average sunshine in September
Slemmestad, Norway
- Average daylight in September: 12h and 54min
The month with the longest days is June (Average daylight: 18h and 36min).
The month with the shortest days is December (Average daylight: 6h and 6min).
- Average sunshine in September: 7h and 30min
The month with the most sunshine is June (Average sunshine: 11h and 24min).
The months with the least sunshine are January and December (Average sunshine: 3h and 12min).
Average sunshine days in September
Slemmestad, Norway
- Average sunshine days in September: 16.5 days
The month with the most sunshine days is December (18.3 days).
The month with the least sunshine days is July (10.6 days).
Average UV index in September
Slemmestad, Norway
- 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 and February (UV index 1).
Average cloud cover in September
Slemmestad, Norway
- Average cloud cover in September: 49
The month with the most cloud cover is February (Cloud cover 65).
The month with the least cloud cover is June (Cloud cover 45).
Average visibility in September
Slemmestad, Norway
- Average visibility in September: 8km
The months with the highest visibility are April, May and June (9km).
The month with the lowest visibility is February (6km).
