Climate averages 1991–2020
Ust’-Ilimsk weather
in September.
A cool, moderately wet month: the 5th warmest and the 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a cool month in Ust’-Ilimsk: daytime highs average 12.1°C and nights cool to about 5.2°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 51 mm of rain on roughly 11 days, which makes September a moderately wet month (the 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 53 min on an average September day.
The nearest other city in this atlas is Bratsk (217 km away). In September its highs average 12.0°C, about as warm as Ust’-Ilimsk, with 42 mm of rain.
Among the 236 cities listed in Russia, Ust’-Ilimsk ranks 220th of 236 for the warmest September highs and joint 71st of 236 for the driest September (rainfall, lowest first). The mean September high of those 236 cities is 16.4°C; Ust’-Ilimsk is 4.3°C cooler than that mean.
From September to October, average highs fall by 9.5°C to 2.6°C, and monthly rainfall falls from 51 mm to 41 mm.
The annual picture
September in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Ust’-Ilimsk climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -18.5°C-24.1°C | -24.1°C | 14 | 5.1 | 7.37 h |
| February | -14.1°C-20.7°C | -20.7°C | 12 | 4.5 | 9.39 h |
| March | -5.0°C-12.5°C | -12.5°C | 19 | 6.3 | 11.812 h |
| April | 3.5°C-4.7°C | -4.7°C | 28 | 7.8 | 14.314 h |
| May | 12.5°C2.6°C | 2.6°C | 43 | 10.6 | 16.717 h |
| June | 20.8°C11.2°C | 11.2°C | 56 | 10.5 | 18.018 h |
| July | 23.6°C15.0°C | 15.0°C | 59 | 10.0 | 17.417 h |
| August | 20.6°C12.6°C | 12.6°C | 57 | 9.9 | 15.415 h |
| September, selected | 12.1°C5.2°C | 5.2°C | 51 | 10.9 | 12.913 h |
| October | 2.6°C-2.8°C | -2.8°C | 41 | 11.4 | 10.410 h |
| November | -9.5°C-15.8°C | -15.8°C | 31 | 9.7 | 8.08 h |
| December | -16.9°C-23.2°C | -23.2°C | 22 | 7.7 | 6.67 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Bratsk in SeptemberRussia · 217 kmHigh 12.0°C · Low 6.8°C · 42 mm rain
- Kansk in SeptemberRussia · 464 kmHigh 13.9°C · Low 5.6°C · 48 mm rain
- Zelenogorsk in SeptemberRussia · 531 kmHigh 13.9°C · Low 5.7°C · 54 mm rain
- Zheleznogorsk (Krasnoyarsk Krai), Russia in SeptemberRussia · 584 kmHigh 14.0°C · Low 5.8°C · 59 mm rain
- Usol’ye-Sibirskoye in SeptemberRussia · 587 kmHigh 15.3°C · Low 5.5°C · 53 mm rain
- Angarsk in SeptemberRussia · 610 kmHigh 15.5°C · Low 5.5°C · 51 mm rain
- Krasnoyarsk in SeptemberRussia · 627 kmHigh 13.9°C · Low 5.7°C · 53 mm rain
- Irkutsk in SeptemberRussia · 643 kmHigh 15.4°C · Low 5.8°C · 61 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Ust’-Ilimsk) is explained once on the Ust’-Ilimsk year overview and on the Sources, method and limits page.