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The weather in Irkutsk in September is very cold with temperatures between 4°C and 15°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Irkutsk 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.
Please note that Irkutsk can expect a few days of snow in September.
Our weather forecast can give you a great sense of what weather to expect in Irkutsk in September 2025.
If you’re planning to visit Irkutsk in the near future, we highly recommend that you review the 14 day weather forecast for Irkutsk before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | -14° / -24° | 2 | 10 | 19 | 20 mm | Awful | Irkutsk in January |
| February | -11° / -23° | 3 | 8 | 17 | 18 mm | Awful | Irkutsk in February |
| March | -2° / -13° | 5 | 7 | 19 | 35 mm | Awful | Irkutsk in March |
| April | 8° / -2° | 5 | 12 | 13 | 48 mm | Bad | Irkutsk in April |
| May | 16° / 3° | 6 | 21 | 4 | 74 mm | Ok | Irkutsk in May |
| June | 24° / 9° | 6 | 24 | 0 | 85 mm | Perfect | Irkutsk in June |
| July | 26° / 12° | 7 | 24 | 0 | 127 mm | Good | Irkutsk in July |
| August | 23° / 10° | 7 | 24 | 0 | 124 mm | Good | Irkutsk in August |
| September | 15° / 4° | 6 | 22 | 2 | 75 mm | Ok | Irkutsk in September |
| October | 6° / -2° | 4 | 17 | 10 | 32 mm | Awful | Irkutsk in October |
| November | -5° / -12° | 3 | 10 | 17 | 25 mm | Awful | Irkutsk in November |
| December | -12° / -20° | 3 | 9 | 19 | 25 mm | Awful | Irkutsk in December |