Irkutsk climate
Irkutsk (Irkutsk Oblast, Russia) has a warm-summer humid continental climate (Köppen Dfb). The average temperature over the year is 1 °C34 °F, and about 418 mm16 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Irkutsk climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | −163 | −25−12 | −20−5 | 110.4 | 31 |
| Feb | −1211 | −22−8 | −171 | 90.4 | 28 |
| Mar | −229 | −139 | −719 | 130.5 | 31 |
| Apr | 949 | −228 | 438 | 220.9 | 25 |
| May | 1763 | 439 | 1051 | 401.6 | 8 |
| Jun | 2577 | 1254 | 1966 | 572.2 | 0 |
| Jul | 2781 | 1559 | 2170 | 853.3 | 0 |
| Aug | 2475 | 1254 | 1865 | 823.2 | 0 |
| Sep | 1661 | 540 | 1051 | 471.8 | 5 |
| Oct | 643 | −326 | 135 | 210.8 | 26 |
| Nov | −523 | −139 | −916 | 150.6 | 30 |
| Dec | −147 | −22−7 | −180 | 160.6 | 31 |
| Year | 2781 | −25−12 | 134 | 41816 | 216 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 96% | 59% | 1.2 | 8:12 |
| Feb | 95% | 56% | 2.3 | 9:49 |
| Mar | 87% | 62% | 3.8 | 11:42 |
| Apr | 64% | 69% | 4.8 | 13:50 |
| May | 61% | 67% | 5.6 | 15:42 |
| Jun | 61% | 68% | 5.9 | 16:45 |
| Jul | 63% | 67% | 5.5 | 16:19 |
| Aug | 68% | 64% | 4.6 | 14:40 |
| Sep | 72% | 65% | 3.4 | 12:34 |
| Oct | 76% | 70% | 2.2 | 10:30 |
| Nov | 85% | 73% | 1.2 | 8:39 |
| Dec | 94% | 67% | 0.8 | 7:43 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Irkutsk is like
The warmest month is July, with an average high of 27 °C81 °F and a low of 15 °C59 °F. The coldest is January, when highs average −16 °C3 °F and lows −25 °C−12 °F. The climate is extremely continental — the average temperature swings by 41.4 °C74.6 °F between the coldest and the warmest month.
Annual precipitation is moderate at about 418 mm16 in. The wettest three-month stretch is June–August, which brings 54% of the annual total. Months with less than 20 mm0.8 in on average: November–March. The wettest month is July (85 mm3.3 in), the driest is February (9 mm0.4 in).
Relative humidity ranges from 61% in May to 96% in January. The clearest skies (lowest average cloud amount, 56%) are typical of February. Average wind speed near the ground ranges from 6 km/h (4 mph) in January to 9 km/h (6 mph) in April. Daylight lasts from about 7.7 hours in December to 16.8 hours in June.
A lasting snow cover is typical in October–March, when the average snow depth in the reanalysis exceeds 10 cm (deepest in February, about 21 cm).
Best time to visit Irkutsk
Based on these averages, the most comfortable months for sightseeing and outdoor activities are June–August: average highs of 24 °C75 °F to 27 °C81 °F with 57 mm2.2 in to 85 mm3.3 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of −16 °C3 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Irkutsk
- Winter (December–February) — highs −163 to −12 °C11 °F, lows −25−12 to −22 °C−7 °F, about 12 mm0.5 in of precipitation a month. Pack heavy insulated clothing, thermal base layers, a warm hat, mittens and insulated boots.
- Spring (March–May) — highs −229 to 17 °C63 °F, lows −139 to 4 °C39 °F, about 25 mm1.0 in of precipitation a month. Pack a warm coat, layers and closed shoes, an extra layer for the cooler mornings and evenings and shoes with good grip, as frost is common.
- Summer (June–August) — highs 2475 to 27 °C81 °F, lows 1254 to 15 °C59 °F, about 75 mm2.9 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an extra layer for the cooler mornings and evenings.
- Autumn (September–November) — highs −523 to 16 °C61 °F, lows −139 to 5 °C40 °F, about 28 mm1.1 in of precipitation a month. Pack a warm coat, layers and closed shoes and shoes with good grip, as frost is common.
How Irkutsk compares
Of the 169 places in Russia covered by World Climates, Irkutsk is the 129th warmest by annual mean temperature and the 153rd wettest by annual precipitation. See all of them on the Russia climate page.
Places in other countries with the most similar temperature and rainfall pattern: Hulunbuir (China, Dwb), Beian (China, Dwb) and Petropavl (Kazakhstan, Dfb).
Nearby places
- Angarsk 39 km · 1 °C34 °F · 457 mm18 in
- Ust-Ordynskiy 65 km · 0 °C32 °F · 347 mm14 in
- Ulan-Ude 232 km · 1 °C33 °F · 310 mm12 in
- Bratsk 461 km · −1 °C30 °F · 525 mm21 in
- Ulan Bator 522 km · 0 °C33 °F · 276 mm11 in
- Chita 628 km · 0 °C31 °F · 374 mm15 in
- Ust-Ilimsk 643 km · −2 °C28 °F · 554 mm22 in
- Kyzyl 677 km · 3 °C37 °F · 290 mm11 in
Frequently asked questions
What is the warmest month in Irkutsk?
July is the warmest month in Irkutsk, with an average high of 27 °C (81 °F) and an average low of 15 °C (59 °F).
What is the coldest month in Irkutsk?
January is the coldest month, with an average high of -16 °C (3 °F) and an average low of -25 °C (-12 °F).
When does it rain the most in Irkutsk?
July is the wettest month with about 85 mm (3.3 in) of precipitation; February is the driest with about 9 mm (0.4 in).
What is the best time to visit Irkutsk?
Judging by long-term averages, the most comfortable months are June–August.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 542 m, while Irkutsk lies at about 415 m. Temperatures on this page were therefore adjusted by +0.8 °C1.5 °F using the standard lapse rate of 6.5 °C per 1,000 m.