Climate and average weather in Irkutsk
In Irkutsk, the summers are warm, showery, and partly cloudy and the winters are frigid, snowy, and partly cloudy.
Over the course of the year, the temperature in Irkutsk typically varies from -24°C to 23°C, and is rarely below -33°C or above 28°C. July is the hottest month of the year, while January is the coldest.
Based on the travel score, the best time of year to visit Irkutsk for warm-weather activities is from mid May to early September.
- Hottest
- Jul
- 23°
- Coldest
- Jan
- -24°
- Wettest
- Aug
- 101 mm
- Driest
- Feb
- 5 mm
- Rain / yr
- 447 mm
- 79 wet days
- Daylight
- 7.5–16.5 h
- shortest–longest
- Elevation
- 415 m
- 52.3°N
- Clearest
- Mar
- 57% cloud
Irkutsk is capital city of Irkutsk Oblast, Siberia, in eastern Russia.
- Density
- 2,252/km²
- people per km²
- Founded
- 1661
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Irkutsk weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around mid May to early September.
Temperature through the year
Daily average highs and lows in Irkutsk, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 4.5 months, from May 8 to September 21, with daily high temperatures above 14°C. The hottest month of the year in Irkutsk is July, with an average high of 23°C and low of 14°C.
The cool season lasts 2.9 months, from November 25 to February 20, with daily high temperatures below -8°C. The coldest month of the year in Irkutsk is January, with an average low of -24°C and high of -15°C.
Days typically run about 10°C warmer than nights, with the widest day–night swing (around 12°C) in May.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | -15 | -9 | 0 | 9 | 16 | 21 | 23 | 21 | 15 | 7 | -4 | -12 |
| Avg low (°C) | -24 | -21 | -12 | -3 | 4 | 10 | 14 | 12 | 6 | -2 | -11 | -20 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | -15 | -24 |
| Feb | -9 | -21 |
| Mar | 0 | -12 |
| Apr | 9 | -3 |
| May | 16 | 4 |
| Jun | 21 | 10 |
| Jul | 23 | 14 |
| Aug | 21 | 12 |
| Sep | 15 | 6 |
| Oct | 7 | -2 |
| Nov | -4 | -11 |
| Dec | -12 | -20 |
How hot and cold Irkutsk really feels
The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.
On the coldest nights, wind chill pulls the feels-like down to about -30°C (around January 21), with roughly 227 freezing days a year (feels-like at or below 0°C) — 152 of them bitterly cold — worst in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | -15 | -10 | 0 | 9 | 16 | 21 | 23 | 21 | 15 | 7 | -4 | -12 |
| Air high (°C) | -15 | -9 | 0 | 9 | 16 | 21 | 23 | 21 | 15 | 7 | -4 | -12 |
| Feels-like low (°C) | -30 | -27 | -18 | -7 | 1 | 9 | 13 | 12 | 4 | -5 | -16 | -26 |
| Air low (°C) | -24 | -21 | -12 | -3 | 4 | 10 | 14 | 12 | 6 | -2 | -11 | -20 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | -15 | -15 | -30 | -24 |
| Feb | -10 | -9 | -27 | -21 |
| Mar | 0 | 0 | -18 | -12 |
| Apr | 9 | 9 | -7 | -3 |
| May | 16 | 16 | 1 | 4 |
| Jun | 21 | 21 | 9 | 10 |
| Jul | 23 | 23 | 13 | 14 |
| Aug | 21 | 21 | 12 | 12 |
| Sep | 15 | 15 | 4 | 6 |
| Oct | 7 | 7 | -5 | -2 |
| Nov | -4 | -4 | -16 | -11 |
| Dec | -12 | -12 | -26 | -20 |
Average hourly temperature in Irkutsk
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on July afternoons, near 23°C, and coldest before dawn in January, near -24°C.
Irkutsk weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | -15° / -24° | 5 | 1.8 | 3.3 | 8 | 0.0 |
| Feb | -10° / -21° | 5 | 1.8 | 3.2 | 9.5 | 0.0 |
| Mar | -0° / -13° | 10 | 3.4 | 4.4 | 11.5 | 0.0 |
| Apr | 9° / -3° | 22 | 5.7 | 3.6 | 13.6 | 1.7 |
| May | 16° / 4° | 38 | 8.9 | 1.4 | 15.4 | 5.0 |
| Jun | 21° / 10° | 65 | 10.3 | 0 | 16.4 | 6.4 |
| Jul | 23° / 14° | 94 | 12.2 | 0 | 16 | 6.5 |
| Aug | 21° / 12° | 101 | 11.6 | 0 | 14.5 | 6.3 |
| Sep | 15° / 6° | 61 | 10.2 | 0.6 | 12.4 | 4.6 |
| Oct | 7° / -2° | 23 | 5.7 | 3.9 | 10.3 | 1.1 |
| Nov | -4° / -11° | 13 | 4 | 5.3 | 8.5 | 0.0 |
| Dec | -13° / -20° | 10 | 3.5 | 5.2 | 7.5 | 0.0 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Irkutsk gets about 447 mm of precipitation a year. On a typical day the chance of rain is some rain, but that rises and falls sharply with the seasons.
The wetter season lasts 5.5 months, from around Apr 25 to Oct 7, peaking in July at about 41% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 13.
August is the wettest month by volume, with 101 mm over about 12 wet days; February is the driest, with 5 mm. Some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 6 | 7 | 11 | 19 | 29 | 35 | 39 | 38 | 33 | 20 | 13 | 11 |
| Rain days | 2 | 2 | 3 | 6 | 9 | 10 | 12 | 12 | 10 | 6 | 4 | 4 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 6 | 2 |
| Feb | 7 | 2 |
| Mar | 11 | 3 |
| Apr | 19 | 6 |
| May | 29 | 9 |
| Jun | 35 | 10 |
| Jul | 39 | 12 |
| Aug | 38 | 12 |
| Sep | 33 | 10 |
| Oct | 20 | 6 |
| Nov | 13 | 4 |
| Dec | 11 | 4 |
Monthly rainfall
Over a full year, Irkutsk collects about 447 mm of rain across 79 wet days — roughly 37 mm in an average month.
It doesn’t fall evenly. August is the wettest month with 101 mm, while February is the driest at just 5 mm. The three wettest months alone bring about 58% of the year’s total, and some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 5 | 5 | 10 | 22 | 38 | 65 | 94 | 101 | 61 | 23 | 13 | 10 |
| Rain days | 2 | 2 | 3 | 6 | 9 | 10 | 12 | 12 | 10 | 6 | 4 | 4 |
| Snow days | 3 | 3 | 4 | 4 | 1 | 0 | 0 | 0 | 1 | 4 | 5 | 5 |
| Rainfall (mm) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 5 | 2 | 3 |
| Feb | 5 | 2 | 3 |
| Mar | 10 | 3 | 4 |
| Apr | 22 | 6 | 4 |
| May | 38 | 9 | 1 |
| Jun | 65 | 10 | 0 |
| Jul | 94 | 12 | 0 |
| Aug | 101 | 12 | 0 |
| Sep | 61 | 10 | 1 |
| Oct | 23 | 6 | 4 |
| Nov | 13 | 4 | 5 |
| Dec | 10 | 4 | 5 |
Snow in Irkutsk
Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.
Irkutsk averages about 31 snowy days a year. Snow season runs roughly Sep 15 to May 28 — about 8.4 months.
November is snowiest, with roughly 5 days of snow and an estimated 14 cm of snowfall. Over the year that adds up to an estimated 94 cm of snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Snow days | 3 | 3 | 4 | 4 | 1 | 0 | 0 | 0 | 1 | 4 | 5 | 5 |
| Snowfall (cm) | 9 | 10 | 13 | 13 | 4 | 0 | 0 | 0 | 3 | 13 | 14 | 14 |
| Snow days | Snowfall (cm) | |
|---|---|---|
| Jan | 3 | 9 |
| Feb | 3 | 10 |
| Mar | 4 | 13 |
| Apr | 4 | 13 |
| May | 1 | 4 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 1 | 3 |
| Oct | 4 | 13 |
| Nov | 5 | 14 |
| Dec | 5 | 14 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Irkutsk, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.
The clearer part of the year begins around December 28 and lasts for 3.0 months, ending around March 29. The clearest month is February, when the sky is clear, mostly clear, or partly cloudy 47% of the time on average.
The cloudier part of the year begins around October 26 and lasts for 2.1 months, ending around December 27. The cloudiest month is November, when it is overcast or mostly cloudy 67% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 47 | 47 | 46 | 40 | 44 | 45 | 41 | 44 | 46 | 45 | 33 | 36 |
| Cloudier (%) | 53 | 53 | 54 | 60 | 56 | 55 | 59 | 56 | 54 | 55 | 67 | 64 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 47 | 53 |
| Feb | 47 | 53 |
| Mar | 46 | 54 |
| Apr | 40 | 60 |
| May | 44 | 56 |
| Jun | 45 | 55 |
| Jul | 41 | 59 |
| Aug | 44 | 56 |
| Sep | 46 | 54 |
| Oct | 45 | 55 |
| Nov | 33 | 67 |
| Dec | 36 | 64 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 12, brings about 16 h 30 min of light; the shortest, around January 1, only 7 h 30 min — a swing of roughly 9 hours.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 8.0 | 9.5 | 11.5 | 13.6 | 15.4 | 16.4 | 16.0 | 14.5 | 12.4 | 10.3 | 8.5 | 7.5 |
| Sunrise (AM) | 9:13 | 8:31 | 7:28 | 6:14 | 5:15 | 4:48 | 5:06 | 5:52 | 6:45 | 7:38 | 8:34 | 9:15 |
| Sunset (PM) | 5:11 | 6:04 | 6:57 | 7:52 | 8:43 | 9:18 | 9:11 | 8:21 | 7:09 | 5:58 | 5:02 | 4:43 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 8.0 | 9:13 | 5:11 |
| Feb | 9.5 | 8:31 | 6:04 |
| Mar | 11.5 | 7:28 | 6:57 |
| Apr | 13.6 | 6:14 | 7:52 |
| May | 15.4 | 5:15 | 8:43 |
| Jun | 16.4 | 4:48 | 9:18 |
| Jul | 16.0 | 5:06 | 9:11 |
| Aug | 14.5 | 5:52 | 8:21 |
| Sep | 12.4 | 6:45 | 7:09 |
| Oct | 10.3 | 7:38 | 5:58 |
| Nov | 8.5 | 8:34 | 5:02 |
| Dec | 7.5 | 9:15 | 4:43 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Irkutsk averages about 8 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 4 and 11 days.
The sunnier stretch runs 3.2 months, from around Dec 27 to Apr 2. The sunniest month is February, with roughly 10 sunny days (mixed).
The greyest month is November, down near 6 sunny days — about 42% fewer than the February peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 10 | 9 | 10 | 7 | 8 | 8 | 8 | 9 | 9 | 9 | 6 | 7 |
| Sky | Mixed | Mixed | Mixed | Gloomy | Gloomy | Mixed | Gloomy | Mixed | Mixed | Mixed | Gloomy | Gloomy |
| Sunny days | Sky | |
|---|---|---|
| Jan | 10 | Mixed |
| Feb | 9 | Mixed |
| Mar | 10 | Mixed |
| Apr | 7 | Gloomy |
| May | 8 | Gloomy |
| Jun | 8 | Mixed |
| Jul | 8 | Gloomy |
| Aug | 9 | Mixed |
| Sep | 9 | Mixed |
| Oct | 9 | Mixed |
| Nov | 6 | Gloomy |
| Dec | 7 | Gloomy |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Irkutsk, how humid it feels changes noticeably over the year.
The more humid part of the year lasts 2.2 months, from around June 21 to August 26. The muggiest month is July, when the air feels humid, muggy or worse about 17% of the time.
The most comfortable stretch runs from around August 27 to June 20, and June is the most comfortable month — the air is dry or comfortable 98% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 100 | 100 | 100 | 100 | 100 | 89 | 44 | 53 | 96 | 100 | 100 | 100 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 0 | 9 | 39 | 38 | 4 | 0 | 0 | 0 |
| Humid (%) | 0 | 0 | 0 | 0 | 0 | 2 | 16 | 9 | 0 | 0 | 0 | 0 |
| Muggy (%) | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | |
|---|---|---|---|---|
| Jan | 100 | 0 | 0 | 0 |
| Feb | 100 | 0 | 0 | 0 |
| Mar | 100 | 0 | 0 | 0 |
| Apr | 100 | 0 | 0 | 0 |
| May | 100 | 0 | 0 | 0 |
| Jun | 89 | 9 | 2 | 0 |
| Jul | 44 | 39 | 16 | 1 |
| Aug | 53 | 38 | 9 | 0 |
| Sep | 96 | 4 | 0 | 0 |
| Oct | 100 | 0 | 0 | 0 |
| Nov | 100 | 0 | 0 | 0 |
| Dec | 100 | 0 | 0 | 0 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Irkutsk is typically calm, near 9 km/h, and varies little with the seasons.
The windier part of the year lasts 3.4 months, from around Mar 11 to Jun 22. The windiest month is April, averaging about 10 km/h (calm).
The calmer part of the year runs from around Nov 10 to Mar 10, with January the calmest month at about 7 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 7 | 8 | 9 | 10 | 10 | 9 | 8 | 9 | 9 | 9 | 8 | 7 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 7 | calm |
| Feb | 8 | calm |
| Mar | 9 | calm |
| Apr | 10 | calm |
| May | 10 | calm |
| Jun | 9 | calm |
| Jul | 8 | calm |
| Aug | 9 | calm |
| Sep | 9 | calm |
| Oct | 9 | calm |
| Nov | 8 | calm |
| Dec | 7 | calm |
Best time to visit Irkutsk
To characterize how pleasant the weather is in Irkutsk throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around late August, Irkutsk is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Irkutsk for general outdoor tourist activities is from mid May to early September, with a peak score in the second week of July.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 0.0 | 0.0 | 0.0 | 1.8 | 5.0 | 6.4 | 6.5 | 6.3 | 4.6 | 1.2 | 0.0 | 0.0 |
| Rating | poor | poor | poor | poor | fair | good | good | good | fair | poor | poor | poor |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 0.0 | poor |
| Feb | 0.0 | poor |
| Mar | 0.0 | poor |
| Apr | 1.8 | poor |
| May | 5.0 | fair |
| Jun | 6.4 | good |
| Jul | 6.5 | good |
| Aug | 6.3 | good |
| Sep | 4.6 | fair |
| Oct | 1.2 | poor |
| Nov | 0.0 | poor |
| Dec | 0.0 | poor |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Irkutsk for hot-weather activities is from mid June to mid August, with a peak score in the second week of July.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Irkutsk, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
For a warm-season trip around July (highs near 23°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near -15°C), pack a warm layer and a heavy coat.
In July, Irkutsk sees daytime highs around 23°C and nights near 14°C. Worth packing: light clothes, rain gear and sun protection. About 12 days see rain.
UV index (midday) in Irkutsk by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Irkutsk peaks around July 12 at about 7 (high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near December 19 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 6 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 1 | 2 | 5 | 5 | 6 | 7 | 5 | 4 | 2 | 1 | 1 |
| Level | Low | Low | Moderate | Moderate | High | High | High | Moderate | Moderate | Low | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 1 | Low |
| Mar | 2 | Moderate |
| Apr | 5 | Moderate |
| May | 5 | High |
| Jun | 6 | High |
| Jul | 7 | High |
| Aug | 5 | Moderate |
| Sep | 4 | Moderate |
| Oct | 2 | Low |
| Nov | 1 | Low |
| Dec | 1 | Low |
Average hourly UV index in Irkutsk
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in July the burn window is concentrated in the middle of the day: about 7.5 hours a day reach index 3 (protection recommended), and 2.5 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 0 | 0 | 0 | 5 | 6.5 | 7.5 | 7.5 | 5.5 | 3 | 0 | 0 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 0 | 0 | 1 | 2.5 | 0 | 0 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 0 | 0 |
| Apr | 5 | 0 |
| May | 6.5 | 0 |
| Jun | 7.5 | 1 |
| Jul | 7.5 | 2.5 |
| Aug | 5.5 | 0 |
| Sep | 3 | 0 |
| Oct | 0 | 0 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Air quality in Irkutsk by month
Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.
Air quality in Irkutsk is worst in May — around 22 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (November, 10 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 15 | 15 | 13 | 17 | 22 | 16 | 18 | 18 | 11 | 12 | 10 | 12 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 15 | Moderate |
| Feb | 15 | Moderate |
| Mar | 13 | Moderate |
| Apr | 17 | Moderate |
| May | 22 | Moderate |
| Jun | 16 | Moderate |
| Jul | 18 | Moderate |
| Aug | 18 | Moderate |
| Sep | 11 | Good |
| Oct | 12 | Good |
| Nov | 10 | Good |
| Dec | 12 | Good |
Growing season
The growing season in Irkutsk typically lasts about 163 days, from around April 29 to October 8 — the span where a frost-free day is more likely than not. It is reliably frost-free from May 19 to September 23.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 0 | 0 | 3 | 26 | 83 | 100 | 100 | 100 | 94 | 33 | 4 | 0 |
| Frost nights | 31 | 28 | 31 | 30 | 18 | 0 | 0 | 0 | 7 | 31 | 30 | 31 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 0 | 31 |
| Feb | 0 | 28 |
| Mar | 3 | 31 |
| Apr | 26 | 30 |
| May | 83 | 18 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 94 | 7 |
| Oct | 33 | 31 |
| Nov | 4 | 30 |
| Dec | 0 | 31 |
Growing degree days
Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Irkutsk banks about 694 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 0 | 0 | 0 | 0 | 21 | 168 | 261 | 209 | 35 | 0 | 0 | 0 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 0 |
| Feb | 0 |
| Mar | 0 |
| Apr | 0 |
| May | 21 |
| Jun | 168 |
| Jul | 261 |
| Aug | 209 |
| Sep | 35 |
| Oct | 0 |
| Nov | 0 |
| Dec | 0 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Irkutsk receives about 3.6 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.9 and 6.2 kWh/m².
The brighter stretch of the year lasts 6.1 months, from around Mar 11 to Sep 13. The brightest month is June, averaging about 6.0 kWh/m² (intense).
The dimmest month is December, down near 0.9 kWh/m² — roughly 85% less than the June peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 1.2 | 2.3 | 3.9 | 5.1 | 6.0 | 6.1 | 5.5 | 4.7 | 3.5 | 2.3 | 1.3 | 0.9 |
| Level | Dim | Moderate | Moderate | Bright | Intense | Intense | Bright | Bright | Moderate | Moderate | Dim | Dim |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 1.2 | Dim |
| Feb | 2.3 | Moderate |
| Mar | 3.9 | Moderate |
| Apr | 5.1 | Bright |
| May | 6.0 | Intense |
| Jun | 6.1 | Intense |
| Jul | 5.5 | Bright |
| Aug | 4.7 | Bright |
| Sep | 3.5 | Moderate |
| Oct | 2.3 | Moderate |
| Nov | 1.3 | Dim |
| Dec | 0.9 | Dim |
Where is Irkutsk?
Irkutsk sits at 52.3°N, 104.3°E, 415 m above sea level, in Russia. The nearest listed city is Markova, 11 km away.
Topography around Irkutsk
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Irkutsk.
Within 3 km, the terrain around Irkutsk has only modest variations in elevation — a maximum elevation change of 104 m around an average of 442 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 204 m; within 80 km, large variations in elevation — a maximum elevation change of 1,089 m.
The land around Irkutsk is covered by artificial surfaces (54%) and trees (27%) within 3 km, trees (58%) within 16 km, and trees (69%) within 80 km.
Russia travel facts
- Travel advisory
- Level 4
- Do Not Travel
- Power plugs
- Type C / F
- 230 V · 50 Hz
- Prices
- ≈ 32% of US
- price level, 2025
- GDP per capita
- $17,547
- 2025
- Happiness
- 5.8 / 10
- World Happiness, 2025
- Safe drinking water
- 76%
- of population, 2024
- Homicide rate
- 6.8
- per 100k, 2021
- Road deaths
- 12
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Moderate
- EF EPI 521
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Irkutsk (52.2957°, 104.2908°, elevation 415 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).