Click on a day for an hourly weather forecast
The temperatures in Lillestrom in September are quite cold with temperatures between 8°C and 16°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Lillestrom 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 Lillestrom in September 2026.
If you’re planning to visit Lillestrom in the near future, we highly recommend that you review the 14 day weather forecast for Lillestrom before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -2° / -7° | 3 | 13 | 15 | 51 mm | Awful | Lillestrom in January |
| February | -1° / -8° | 4 | 11 | 14 | 45 mm | Awful | Lillestrom in February |
| March | 3° / -5° | 6 | 16 | 10 | 46 mm | Awful | Lillestrom in March |
| April | 10° / 2° | 4 | 23 | 3 | 39 mm | Bad | Lillestrom in April |
| May | 15° / 5° | 7 | 23 | 1 | 85 mm | Ok | Lillestrom in May |
| June | 19° / 9° | 7 | 23 | 0 | 89 mm | Ok | Lillestrom in June |
| July | 21° / 11° | 7 | 24 | 0 | 99 mm | Ok | Lillestrom in July |
| August | 20° / 11° | 7 | 24 | 0 | 94 mm | Ok | Lillestrom in August |
| September | 16° / 8° | 5 | 25 | 0 | 69 mm | Good | Lillestrom in September |
| October | 10° / 4° | 7 | 23 | 1 | 68 mm | Bad | Lillestrom in October |
| November | 4° / 0° | 6 | 18 | 6 | 67 mm | Awful | Lillestrom in November |
| December | -1° / -5° | 6 | 14 | 11 | 58 mm | Awful | Lillestrom in December |