Click on a day for an hourly weather forecast
The temperatures in Grimsby in September are usually low and can range between 12°C and 17°C.
You can expect about 3 to 8 days of rain in Grimsby 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 Grimsby in September 2025.
If you’re planning to visit Grimsby in the near future, we highly recommend that you review the 14 day weather forecast for Grimsby before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 6° / 3° | 8 | 20 | 4 | 60 mm | Awful | Grimsby in January |
| February | 7° / 3° | 7 | 17 | 4 | 63 mm | Awful | Grimsby in February |
| March | 9° / 4° | 6 | 24 | 2 | 57 mm | Bad | Grimsby in March |
| April | 11° / 5° | 4 | 25 | 1 | 44 mm | Ok | Grimsby in April |
| May | 14° / 8° | 6 | 25 | 0 | 70 mm | Good | Grimsby in May |
| June | 16° / 11° | 6 | 24 | 0 | 91 mm | Good | Grimsby in June |
| July | 19° / 13° | 6 | 25 | 0 | 93 mm | Good | Grimsby in July |
| August | 20° / 14° | 5 | 26 | 0 | 79 mm | Good | Grimsby in August |
| September | 17° / 12° | 4 | 26 | 0 | 59 mm | Good | Grimsby in September |
| October | 14° / 10° | 7 | 24 | 0 | 84 mm | Ok | Grimsby in October |
| November | 10° / 6° | 7 | 22 | 1 | 78 mm | Bad | Grimsby in November |
| December | 7° / 4° | 6 | 23 | 2 | 69 mm | Bad | Grimsby in December |