Click on a day for an hourly weather forecast
The temperatures in Grimstad in September are usually low and can range between 11°C and 16°C.
You can expect about 3 to 8 days of rain in Grimstad during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Grimstad in September 2025.
If you’re planning to visit Grimstad in the near future, we highly recommend that you review the 14 day weather forecast for Grimstad before you arrive.
Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
---|---|---|---|---|---|---|---|
January | 2° / -1° | 6 | 14 | 11 | 116 mm | Awful | Grimstad in January |
February | 2° / -2° | 7 | 11 | 11 | 108 mm | Awful | Grimstad in February |
March | 5° / 0° | 6 | 19 | 6 | 76 mm | Awful | Grimstad in March |
April | 9° / 4° | 5 | 24 | 1 | 48 mm | Ok | Grimstad in April |
May | 13° / 8° | 7 | 24 | 0 | 85 mm | Bad | Grimstad in May |
June | 17° / 11° | 6 | 24 | 0 | 83 mm | Good | Grimstad in June |
July | 19° / 13° | 6 | 25 | 0 | 89 mm | Good | Grimstad in July |
August | 19° / 13° | 7 | 24 | 0 | 130 mm | Ok | Grimstad in August |
September | 16° / 11° | 7 | 23 | 0 | 126 mm | Ok | Grimstad in September |
October | 11° / 7° | 9 | 21 | 0 | 153 mm | Bad | Grimstad in October |
November | 7° / 4° | 11 | 16 | 4 | 140 mm | Awful | Grimstad in November |
December | 4° / 1° | 10 | 14 | 7 | 133 mm | Awful | Grimstad in December |