Climate averages 1991–2020
Irkutsk weather
by month.
See how the year changes. July has the highest average daily maximum; February has the lowest average monthly precipitation.
Long-term climate patterns, not a forecast for a particular trip.
Across the year Irkutsk averages a daytime high of 6.8°C and a nighttime low of -3.6°C, with about 447 mm of precipitation on roughly 79 days. July is the warmest month (average high 24.6°C) and January the coolest (-13.8°C). August is the wettest month with 101 mm; February is the driest with 5.2 mm.
The annual picture
A year in Irkutsk
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
Irkutsk climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | -13.8°C-22.9°C | -22.9°C | 5.5 | 1.9 | 8.38 h |
| February | -8.2°C-20.0°C | -20.0°C | 5.2 | 1.8 | 9.910 h |
| March | 0.2°C-12.0°C | -12.0°C | 10 | 3.4 | 11.812 h |
| April | 9.4°C-2.7°C | -2.7°C | 22 | 5.6 | 13.914 h |
| May | 16.8°C3.3°C | 3.3°C | 38 | 8.9 | 15.716 h |
| June | 22.8°C10.7°C | 10.7°C | 65 | 10.3 | 16.717 h |
| July | 24.6°C14.0°C | 14.0°C | 94 | 12.2 | 16.316 h |
| August | 22.2°C12.4°C | 12.4°C | 101 | 11.6 | 14.715 h |
| September | 15.4°C5.8°C | 5.8°C | 61 | 10.2 | 12.713 h |
| October | 6.9°C-1.8°C | -1.8°C | 23 | 5.7 | 10.711 h |
| November | -3.5°C-11.0°C | -11.0°C | 13 | 4.0 | 8.89 h |
| December | -11.4°C-19.4°C | -19.4°C | 9.5 | 3.5 | 7.88 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
Nearby cities
- AngarskRussia · 39 kmHigh 6.6°C · Low -4.2°C · 382 mm precipitation a year
- Usol’ye-SibirskoyeRussia · 67 kmHigh 6.3°C · Low -4.3°C · 400 mm precipitation a year
- Ulan-UdeRussia · 232 kmHigh 6.5°C · Low -4.9°C · 295 mm precipitation a year
- DarhanMongolia · 333 kmHigh 8.8°C · Low -3.3°C · 327 mm precipitation a year
- ErdenetMongolia · 363 kmHigh 6.6°C · Low -3.9°C · 374 mm precipitation a year
- BratskRussia · 461 kmHigh 2.7°C · Low -3.6°C · 353 mm precipitation a year
- Ulan BatorMongolia · 522 kmHigh 6.7°C · Low -5.4°C · 314 mm precipitation a year
- ChitaRussia · 628 kmHigh 5.5°C · Low -5.8°C · 348 mm precipitation a year
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 limitsWhat do the high and low temperatures mean?
We average the daily maximum and daily minimum for each calendar month over 1991–2020. They are not record extremes, a forecast range or temperatures at a fixed time of day.
How is a rain day counted?
A local calendar day (standard time, UTC+8, no daylight saving) with at least 1 mm of total precipitation counts as one rain day. We count these for each year and month, then average across 30 years. The average does not predict which days will be wet.
Where do the numbers come from?
ERA5-Land (temperature) and ERA5 (precipitation) reanalysis from the Copernicus Climate Change Service, read from the Open-Meteo open-data archive. Temperature comes from the 0.1° model cell at 52.30°, 104.30° (1 km from the city centre), adjusted up by 0.3°C for the difference between the city's elevation (415 m) and the cell's (460 m). Rain comes from the 0.25° cell at 52.25°, 104.25°. These are model estimates, not weather-station readings; coast, hills and city streets can differ.
Does this page show sunshine, humidity or sea temperature?
No. The data used here contain air temperature and precipitation only. Daylight hours are calculated from the city's latitude (sunrise to sunset), not measured sunshine.