Click on a day for an hourly weather forecast
The temperatures in Northampton in September are usually low and can range between 11°C and 19°C.
You can expect about 3 to 8 days of rain in Northampton 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 Northampton in September 2025.
If you’re planning to visit Northampton in the near future, we highly recommend that you review the 14 day weather forecast for Northampton before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 6° / 1° | 6 | 21 | 4 | 47 mm | Awful | Northampton in January |
| February | 7° / 2° | 7 | 16 | 5 | 48 mm | Bad | Northampton in February |
| March | 10° / 3° | 5 | 25 | 1 | 44 mm | Ok | Northampton in March |
| April | 13° / 4° | 4 | 26 | 0 | 41 mm | Ok | Northampton in April |
| May | 16° / 7° | 5 | 26 | 0 | 66 mm | Good | Northampton in May |
| June | 19° / 10° | 5 | 25 | 0 | 75 mm | Good | Northampton in June |
| July | 21° / 12° | 5 | 26 | 0 | 73 mm | Good | Northampton in July |
| August | 21° / 13° | 5 | 26 | 0 | 72 mm | Good | Northampton in August |
| September | 19° / 11° | 3 | 27 | 0 | 39 mm | Good | Northampton in September |
| October | 14° / 8° | 5 | 26 | 0 | 58 mm | Good | Northampton in October |
| November | 10° / 5° | 6 | 23 | 1 | 52 mm | Ok | Northampton in November |
| December | 7° / 3° | 6 | 22 | 2 | 60 mm | Bad | Northampton in December |