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The weather in Aosta Valley in September is very cold with temperatures between 0°C and 13°C, warm clothes are a must.
You can expect rain for roughly half of the month of September in Aosta Valley. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
You can expect a few days of snow in Aosta Valley during September. It’s important to get out your snow boots and warm mittens to stay warm while you explore Aosta Valley.
Our weather forecast can give you a great sense of what weather to expect in Aosta Valley in September 2025.
If you’re planning to visit Aosta Valley in the near future, we highly recommend that you review the 14 day weather forecast for Aosta Valley before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -4° / -16° | 2 | 8 | 21 | 116 mm | Awful | Aosta Valley in January |
| February | -3° / -16° | 3 | 5 | 21 | 114 mm | Awful | Aosta Valley in February |
| March | 0° / -13° | 6 | 4 | 23 | 127 mm | Awful | Aosta Valley in March |
| April | 4° / -8° | 9 | 3 | 20 | 185 mm | Awful | Aosta Valley in April |
| May | 8° / -4° | 18 | 4 | 12 | 272 mm | Awful | Aosta Valley in May |
| June | 14° / 0° | 19 | 10 | 2 | 249 mm | Bad | Aosta Valley in June |
| July | 17° / 2° | 16 | 14 | 1 | 219 mm | Ok | Aosta Valley in July |
| August | 17° / 2° | 15 | 16 | 0 | 201 mm | Ok | Aosta Valley in August |
| September | 13° / 0° | 12 | 16 | 3 | 129 mm | Awful | Aosta Valley in September |
| October | 8° / -5° | 7 | 17 | 8 | 126 mm | Awful | Aosta Valley in October |
| November | 2° / -10° | 4 | 9 | 17 | 183 mm | Awful | Aosta Valley in November |
| December | -3° / -15° | 1 | 11 | 18 | 101 mm | Awful | Aosta Valley in December |