Climate and average weather in Cluj-Napoca
In Cluj-Napoca, the summers are warm, showery, and mostly clear and the winters are very cold, snowy, and partly cloudy.
Over the course of the year, the temperature in Cluj-Napoca typically varies from -6°C to 25°C, and is rarely below -15°C or above 30°C. August is the hottest month of the year, while January is the coldest.
Based on the travel score, the best time of year to visit Cluj-Napoca for warm-weather activities is from early June to early October.
- Hottest
- Aug
- 25°
- Coldest
- Jan
- -6°
- Wettest
- Jun
- 107 mm
- Driest
- Jan
- 34 mm
- Rain / yr
- 781 mm
- 136 wet days
- Daylight
- 8.3–15.7 h
- shortest–longest
- Elevation
- 352 m
- 46.8°N
- Clearest
- Aug
- 45% cloud
Cluj-Napoca is city and seat of Cluj County in northwestern Romania.
- Air quality
- Elevated
- PM2.5 17.8 µg/m³ · 2017
- Density
- 1,597/km²
- people per km²
- Founded
- 1213
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Cluj-Napoca 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 early June to early October.
Temperature through the year
Daily average highs and lows in Cluj-Napoca, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 4.1 months, from May 18 to September 19, with daily high temperatures above 19°C. The hottest month of the year in Cluj-Napoca is August, with an average high of 25°C and low of 13°C.
The cool season lasts 3.2 months, from November 25 to February 28, with daily high temperatures below 5°C. The coldest month of the year in Cluj-Napoca is January, with an average low of -6°C and high of 1°C.
Days typically run about 9°C warmer than nights, with the widest day–night swing (around 12°C) in August.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 1 | 3 | 8 | 14 | 19 | 22 | 24 | 25 | 20 | 14 | 8 | 2 |
| Avg low (°C) | -6 | -5 | -1 | 4 | 8 | 12 | 13 | 13 | 9 | 4 | 0 | -4 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | 1 | -6 |
| Feb | 3 | -5 |
| Mar | 8 | -1 |
| Apr | 14 | 4 |
| May | 19 | 8 |
| Jun | 22 | 12 |
| Jul | 24 | 13 |
| Aug | 25 | 13 |
| Sep | 20 | 9 |
| Oct | 14 | 4 |
| Nov | 8 | 0 |
| Dec | 2 | -4 |
How hot and cold Cluj-Napoca 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 -10°C (around January 30), with roughly 160 freezing days a year (feels-like at or below 0°C), worst in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | 1 | 3 | 8 | 14 | 19 | 22 | 24 | 24 | 20 | 14 | 8 | 1 |
| Air high (°C) | 1 | 3 | 8 | 14 | 19 | 22 | 24 | 25 | 20 | 14 | 8 | 2 |
| Feels-like low (°C) | -9 | -8 | -4 | 2 | 7 | 12 | 13 | 13 | 8 | 2 | -2 | -7 |
| Air low (°C) | -6 | -5 | -1 | 4 | 8 | 12 | 13 | 13 | 9 | 4 | 0 | -4 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | 1 | 1 | -9 | -6 |
| Feb | 3 | 3 | -8 | -5 |
| Mar | 8 | 8 | -4 | -1 |
| Apr | 14 | 14 | 2 | 4 |
| May | 19 | 19 | 7 | 8 |
| Jun | 22 | 22 | 12 | 12 |
| Jul | 24 | 24 | 13 | 13 |
| Aug | 24 | 25 | 13 | 13 |
| Sep | 20 | 20 | 8 | 9 |
| Oct | 14 | 14 | 2 | 4 |
| Nov | 8 | 8 | -2 | 0 |
| Dec | 1 | 2 | -7 | -4 |
Average hourly temperature in Cluj-Napoca
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 August afternoons, near 25°C, and coldest before dawn in January, near -6°C.
Cluj-Napoca 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 | 1° / -6° | 34 | 8 | 6.5 | 8.8 | 0.0 |
| Feb | 3° / -5° | 35 | 9.2 | 5.8 | 10 | 0.0 |
| Mar | 8° / -1° | 49 | 10 | 3.8 | 11.6 | 1.5 |
| Apr | 14° / 4° | 68 | 12.6 | 1.3 | 13.3 | 3.9 |
| May | 19° / 8° | 89 | 15.9 | 0 | 14.8 | 5.3 |
| Jun | 22° / 12° | 107 | 16 | 0 | 15.6 | 5.8 |
| Jul | 24° / 13° | 102 | 15.6 | 0 | 15.3 | 6.2 |
| Aug | 25° / 13° | 84 | 12.4 | 0 | 14 | 6.8 |
| Sep | 20° / 9° | 71 | 10.3 | 0 | 12.4 | 6.2 |
| Oct | 14° / 4° | 56 | 9 | 0.6 | 10.6 | 4.3 |
| Nov | 8° / 0° | 42 | 8.6 | 3 | 9.2 | 1.2 |
| Dec | 2° / -4° | 43 | 8.8 | 5.6 | 8.4 | 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.
Cluj-Napoca gets about 781 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.
The wetter season lasts 4.8 months, from around Apr 4 to Aug 28, peaking in June at about 54% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 11.
June is the wettest month by volume, with 107 mm over about 16 wet days; January is the driest, with 34 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 (%) | 26 | 33 | 32 | 42 | 50 | 53 | 50 | 40 | 34 | 29 | 29 | 28 |
| Rain days | 8 | 9 | 10 | 13 | 16 | 16 | 16 | 12 | 10 | 9 | 9 | 9 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 26 | 8 |
| Feb | 33 | 9 |
| Mar | 32 | 10 |
| Apr | 42 | 13 |
| May | 50 | 16 |
| Jun | 53 | 16 |
| Jul | 50 | 16 |
| Aug | 40 | 12 |
| Sep | 34 | 10 |
| Oct | 29 | 9 |
| Nov | 29 | 9 |
| Dec | 28 | 9 |
Monthly rainfall
Over a full year, Cluj-Napoca collects about 781 mm of rain across 136 wet days — roughly 65 mm in an average month.
It doesn’t fall evenly. June is the wettest month with 107 mm, while January is the driest at just 34 mm. The three wettest months alone bring about 38% 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) | 34 | 35 | 49 | 68 | 89 | 107 | 102 | 84 | 71 | 56 | 42 | 43 |
| Rain days | 8 | 9 | 10 | 13 | 16 | 16 | 16 | 12 | 10 | 9 | 9 | 9 |
| Snow days | 7 | 6 | 4 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 3 | 6 |
| Rainfall (mm) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 34 | 8 | 7 |
| Feb | 35 | 9 | 6 |
| Mar | 49 | 10 | 4 |
| Apr | 68 | 13 | 1 |
| May | 89 | 16 | 0 |
| Jun | 107 | 16 | 0 |
| Jul | 102 | 16 | 0 |
| Aug | 84 | 12 | 0 |
| Sep | 71 | 10 | 0 |
| Oct | 56 | 9 | 1 |
| Nov | 42 | 9 | 3 |
| Dec | 43 | 9 | 6 |
Snow in Cluj-Napoca
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.
Cluj-Napoca averages about 27 snowy days a year. Snow season runs roughly Oct 13 to Apr 28 — about 6.5 months.
January is snowiest, with roughly 6 days of snow and an estimated 22 cm of snowfall. Over the year that adds up to an estimated 105 cm of snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Snow days | 7 | 6 | 4 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | 3 | 6 |
| Snowfall (cm) | 22 | 25 | 13 | 9 | 0 | 0 | 0 | 0 | 0 | 3 | 12 | 21 |
| Snow days | Snowfall (cm) | |
|---|---|---|
| Jan | 7 | 22 |
| Feb | 6 | 25 |
| Mar | 4 | 13 |
| Apr | 1 | 9 |
| May | 0 | 0 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 0 | 0 |
| Oct | 1 | 3 |
| Nov | 3 | 12 |
| Dec | 6 | 21 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Cluj-Napoca, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.
The clearer part of the year begins around May 31 and lasts for 5.2 months, ending around November 5. The clearest month is August, when the sky is clear, mostly clear, or partly cloudy 68% of the time on average.
The cloudier part of the year begins around November 6 and lasts for 5.6 months, ending around April 24. The cloudiest month is February, when it is overcast or mostly cloudy 65% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 39 | 35 | 39 | 44 | 44 | 54 | 62 | 68 | 53 | 49 | 42 | 37 |
| Cloudier (%) | 61 | 65 | 61 | 56 | 56 | 46 | 38 | 32 | 47 | 51 | 58 | 63 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 39 | 61 |
| Feb | 35 | 65 |
| Mar | 39 | 61 |
| Apr | 44 | 56 |
| May | 44 | 56 |
| Jun | 54 | 46 |
| Jul | 62 | 38 |
| Aug | 68 | 32 |
| Sep | 53 | 47 |
| Oct | 49 | 51 |
| Nov | 42 | 58 |
| Dec | 37 | 63 |
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 19, brings about 15 h 42 min of light; the shortest, around December 18, only 8 h 18 min — a swing of roughly 7 h 24 min.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 8.8 | 10.0 | 11.6 | 13.3 | 14.8 | 15.6 | 15.3 | 14.0 | 12.4 | 10.6 | 9.2 | 8.4 |
| Sunrise (AM) | 8:13 | 7:40 | 6:48 | 5:46 | 4:57 | 4:37 | 4:52 | 5:29 | 6:10 | 6:52 | 7:37 | 8:11 |
| Sunset (PM) | 4:57 | 5:40 | 6:23 | 7:06 | 7:46 | 8:15 | 8:11 | 7:31 | 6:30 | 5:30 | 4:45 | 4:33 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 8.8 | 8:13 | 4:57 |
| Feb | 10.0 | 7:40 | 5:40 |
| Mar | 11.6 | 6:48 | 6:23 |
| Apr | 13.3 | 5:46 | 7:06 |
| May | 14.8 | 4:57 | 7:46 |
| Jun | 15.6 | 4:37 | 8:15 |
| Jul | 15.3 | 4:52 | 8:11 |
| Aug | 14.0 | 5:29 | 7:31 |
| Sep | 12.4 | 6:10 | 6:30 |
| Oct | 10.6 | 6:52 | 5:30 |
| Nov | 9.2 | 7:37 | 4:45 |
| Dec | 8.4 | 8:11 | 4:33 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Cluj-Napoca averages about 9 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 7 and 15 days.
The sunnier stretch runs 4.8 months, from around Jun 20 to Nov 11. The sunniest month is August, with roughly 14 sunny days (mixed).
The greyest month is February, down near 7 sunny days — about 52% fewer than the August peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 8 | 6 | 7 | 8 | 8 | 9 | 12 | 14 | 11 | 10 | 8 | 7 |
| Sky | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy | Mixed | Mixed | Mixed | Mixed | Mixed | Mixed | Gloomy |
| Sunny days | Sky | |
|---|---|---|
| Jan | 8 | Gloomy |
| Feb | 6 | Gloomy |
| Mar | 7 | Gloomy |
| Apr | 8 | Gloomy |
| May | 8 | Gloomy |
| Jun | 9 | Mixed |
| Jul | 12 | Mixed |
| Aug | 14 | Mixed |
| Sep | 11 | Mixed |
| Oct | 10 | Mixed |
| Nov | 8 | Mixed |
| 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 Cluj-Napoca, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 2.9 months, from around June 6 to September 2. The muggiest month is July, when the air feels humid, muggy or worse about 25% of the time.
The most comfortable stretch runs from around September 3 to June 5, and May is the most comfortable month — the air is dry or comfortable 100% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 100 | 100 | 100 | 100 | 92 | 53 | 34 | 37 | 84 | 98 | 100 | 100 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 8 | 34 | 40 | 45 | 15 | 2 | 0 | 0 |
| Humid (%) | 0 | 0 | 0 | 0 | 0 | 12 | 24 | 17 | 1 | 0 | 0 | 0 |
| Muggy (%) | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 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 | 92 | 8 | 0 | 0 |
| Jun | 53 | 34 | 12 | 1 |
| Jul | 34 | 40 | 24 | 1 |
| Aug | 37 | 45 | 17 | 1 |
| Sep | 84 | 15 | 1 | 0 |
| Oct | 98 | 2 | 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.
Wind in Cluj-Napoca is steady company: average speeds sit near 7 km/h — calm — in every month of the year, with no meaningful windy or calm season.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 7 | 8 | 9 | 8 | 7 | 7 | 7 | 6 | 7 | 7 | 7 | 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 | 8 | calm |
| May | 7 | calm |
| Jun | 7 | calm |
| Jul | 7 | calm |
| Aug | 6 | calm |
| Sep | 7 | calm |
| Oct | 7 | calm |
| Nov | 7 | calm |
| Dec | 7 | calm |
Best time to visit Cluj-Napoca
To characterize how pleasant the weather is in Cluj-Napoca throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around mid June, Cluj-Napoca is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.
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 Cluj-Napoca for general outdoor tourist activities is from early June to early October, with a peak score in the third week of August.
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 | 1.5 | 3.9 | 5.3 | 5.8 | 6.2 | 6.7 | 6.2 | 4.3 | 1.3 | 0.0 |
| Rating | poor | poor | poor | fair | fair | good | good | good | good | fair | poor | poor |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 0.0 | poor |
| Feb | 0.0 | poor |
| Mar | 1.5 | poor |
| Apr | 3.9 | fair |
| May | 5.3 | fair |
| Jun | 5.8 | good |
| Jul | 6.2 | good |
| Aug | 6.7 | good |
| Sep | 6.2 | good |
| Oct | 4.3 | fair |
| Nov | 1.3 | 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 Cluj-Napoca for hot-weather activities is from late June to late August, with a peak score in the second week of August.
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 Cluj-Napoca, 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 August (highs near 25°C), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 1°C), pack a warm layer, a heavy coat and rain gear.
In August, Cluj-Napoca sees daytime highs around 25°C and nights near 13°C. Worth packing: light clothes, rain gear and sun protection. About 12 days see rain.
UV index (midday) in Cluj-Napoca 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 Cluj-Napoca peaks around July 15 at about 8 (very high) — sunscreen and a hat are worth it in the middle of the day. It bottoms out near January 1 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 7 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 1 | 2 | 3 | 7 | 6 | 8 | 8 | 8 | 5 | 3 | 2 | 1 |
| Level | Low | Low | Moderate | High | High | Very high | Very high | Very high | Moderate | Moderate | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 1 | Low |
| Feb | 2 | Low |
| Mar | 3 | Moderate |
| Apr | 7 | High |
| May | 6 | High |
| Jun | 8 | Very high |
| Jul | 8 | Very high |
| Aug | 8 | Very high |
| Sep | 5 | Moderate |
| Oct | 3 | Moderate |
| Nov | 2 | Low |
| Dec | 1 | Low |
Average hourly UV index in Cluj-Napoca
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 8 hours a day reach index 3 (protection recommended), and 4.5 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 | 2 | 7 | 6.5 | 8 | 8 | 7.5 | 5 | 0 | 0 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 2.5 | 0 | 4 | 4.5 | 4 | 0 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 2 | 0 |
| Apr | 7 | 2.5 |
| May | 6.5 | 0 |
| Jun | 8 | 4 |
| Jul | 8 | 4.5 |
| Aug | 7.5 | 4 |
| Sep | 5 | 0 |
| Oct | 0 | 0 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Air quality in Cluj-Napoca 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 Cluj-Napoca is worst in April — around 24 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (December, 11 µg/m³).
Seasonal pattern from CAMS reanalysis, scaled to Cluj-Napoca's WHO annual average of 17.8 µg/m³.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 15 | 17 | 22 | 24 | 22 | 22 | 21 | 19 | 15 | 12 | 13 | 11 |
| Level | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 15 | Moderate |
| Feb | 17 | Moderate |
| Mar | 22 | Moderate |
| Apr | 24 | Moderate |
| May | 22 | Moderate |
| Jun | 22 | Moderate |
| Jul | 21 | Moderate |
| Aug | 19 | Moderate |
| Sep | 15 | Moderate |
| Oct | 12 | Moderate |
| Nov | 13 | Moderate |
| Dec | 11 | Good |
Growing season
The growing season in Cluj-Napoca typically lasts about 238 days, from around March 24 to November 16 — the span where a frost-free day is more likely than not. It is reliably frost-free from April 20 to October 11.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 14 | 20 | 42 | 85 | 100 | 100 | 100 | 100 | 100 | 84 | 50 | 19 |
| Frost nights | 31 | 28 | 31 | 20 | 0 | 0 | 0 | 0 | 0 | 21 | 30 | 31 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 14 | 31 |
| Feb | 20 | 28 |
| Mar | 42 | 31 |
| Apr | 85 | 20 |
| May | 100 | 0 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 100 | 0 |
| Oct | 84 | 21 |
| Nov | 50 | 30 |
| Dec | 19 | 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. Cluj-Napoca banks about 1,019 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 | 10 | 114 | 214 | 272 | 269 | 129 | 11 | 0 | 0 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 0 |
| Feb | 0 |
| Mar | 0 |
| Apr | 10 |
| May | 114 |
| Jun | 214 |
| Jul | 272 |
| Aug | 269 |
| Sep | 129 |
| Oct | 11 |
| 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.
Cluj-Napoca receives about 3.6 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 1.1 and 5.9 kWh/m².
The brighter stretch of the year lasts 6.1 months, from around Mar 18 to Sep 18. The brightest month is June, averaging about 5.8 kWh/m² (bright).
The dimmest month is December, down near 1.1 kWh/m² — roughly 80% less than the June peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 1.4 | 2.2 | 3.5 | 4.8 | 5.5 | 5.8 | 5.7 | 5.1 | 3.7 | 2.5 | 1.6 | 1.1 |
| Level | Dim | Moderate | Moderate | Bright | Bright | Bright | Bright | Bright | Moderate | Moderate | Dim | Dim |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 1.4 | Dim |
| Feb | 2.2 | Moderate |
| Mar | 3.5 | Moderate |
| Apr | 4.8 | Bright |
| May | 5.5 | Bright |
| Jun | 5.8 | Bright |
| Jul | 5.7 | Bright |
| Aug | 5.1 | Bright |
| Sep | 3.7 | Moderate |
| Oct | 2.5 | Moderate |
| Nov | 1.6 | Dim |
| Dec | 1.1 | Dim |
Where is Cluj-Napoca?
Cluj-Napoca sits at 46.8°N, 23.6°E, 352 m above sea level, in Romania. The nearest listed city is Turda, 26 km away.
Topography around Cluj-Napoca
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Cluj-Napoca.
Within 3 km, the terrain around Cluj-Napoca has only modest variations in elevation — a maximum elevation change of 202 m around an average of 375 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 546 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,669 m.
The land around Cluj-Napoca is covered by artificial surfaces (61%) and trees (24%) within 3 km, grassland (45%), trees (25%) and cropland (21%) within 16 km, and trees (43%), grassland (35%) and cropland (20%) within 80 km.
Romania travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type C / F
- 230 V · 50 Hz
- Prices
- ≈ 44% of US
- price level, 2025
- GDP per capita
- $22,538
- 2025
- Happiness
- 6.6 / 10
- World Happiness, 2025
- Safe drinking water
- 82%
- of population, 2024
- Homicide rate
- 1.1
- per 100k, 2023
- Road deaths
- 10.3
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Very high
- EF EPI 605
- 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 Cluj-Napoca (46.7667°, 23.6°, elevation 352 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).