September weather forecastFredrikstad, Norway
September
Weather in September
The fall season announces its presence in September, registering a definitive dip in temperatures. The sea,however, maintains its warmth at 15.8 degrees for late-season swimmers. Daylight begins to noticeably shorten, giving way to longer evenings. Overall, this month marks the onset of autumn, transition to cooler temperatures and reduction in hours of sunshine. Despite the changes, the city maintains an attractive weather for outdoor activities.Temperature
In Fredrikstad, the average high-temperature in September drops from a pleasant 20°C (68°F) in August to a refreshing 15°C (59°F). During September, the nighttime temperature averages to a chilly 8°C (46.4°F).Rainfall
In Fredrikstad, Norway, in September, it is raining for 16 days, with typically 90mm (3.54") of accumulated precipitation. Throughout the year, there are 179 rainfall days, and 808mm (31.81") of precipitation is accumulated.Sea temperature
In Fredrikstad, in September, the average water temperature is 15.8°C (60.4°F).Note: Swimming in water at 15.8°C (60.4°F) is not a pleasing experience for the majority. As the temperature descends from 21°C (69.8°F) to 15°C (59°F), controlling breathing becomes increasingly hard.
Daylight
In Fredrikstad, Norway, the average length of the day in September is 12h and 50min.On the first day of September, sunrise is at 06:14 and sunset at 20:17. On the last day of the month, sunrise is at 07:20 and sunset at 18:51 CEST.
Sunshine
In Fredrikstad, Norway, the average sunshine in September is 5h.UV index
In September, the average daily maximum UV index in Fredrikstad, Norway, is 3. A UV Index reading of 3 to 5 represents a moderate threat to health from exposure to the Sun's UV radiation for the average person.Note: In September, the maximum UV index of 3 suggests this advice:
Undertake protective steps - Preventing sun damage is advised. The most potent solar radiation is around mid-day, so one should minimize exposure to direct sunlight during this period. Prioritize a wide-brim hat for comprehensive sun defense for your face, neck, eyes, and ears.
Published by: Weather Atlas | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in September
Fredrikstad, Norway
- Average high temperature in September: 15°C
The warmest month (with the highest average high temperature) is July (21°C).
The months with the lowest average high temperature are January and February (0°C).
- Average low temperature in September: 8°C
The month with the highest average low temperature is July (12°C).
The coldest month (with the lowest average low temperature) is February (-7°C).
Average rainfall in September
Fredrikstad, Norway
- Average rainfall in September: 90mm
The wettest month (with the highest rainfall) is October (104mm).
The driest months (with the least rainfall) are February and April (42mm).
Average rainfall days in September
Fredrikstad, Norway
- Average rainfall days in September: 16 days
The month with the highest number of rainy days is November (18 days).
The month with the least rainy days is April (12 days).
Average sea temperature in September
Fredrikstad, Norway
- Average sea temperature in September: 15.8°C
The best month for swimming (with the highest average sea temperature) is August (18.4°C).
The coldest month (with the lowest average sea temperature) is March (2.8°C).
Average daylight in September /
Average sunshine in September
Fredrikstad, Norway
- Average daylight in September: 12h and 48min
The month with the longest days is June (Average daylight: 18h and 24min).
The month with the shortest days is December (Average daylight: 6h and 18min).
- Average sunshine in September: 5h
The month with the most sunshine is June (Average sunshine: 9h).
The months with the least sunshine are January and December (Average sunshine: 1h).
Average UV index in September
Fredrikstad, Norway
- Average UV index in September: 3
The months with the highest UV index are June and July (UV index 5).
The months with the lowest UV index are January, November and December (UV index 0).





