Climate and average weather in Hyesan
In Hyesan, the summers are warm, wet, and mostly cloudy and the winters are frigid, snowy, and mostly clear.
Over the course of the year, the temperature in Hyesan typically varies from -22°C to 23°C, and is rarely below -29°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 Hyesan for warm-weather activities is from late May to late September.
- Hottest
- Jul
- 23°
- Coldest
- Jan
- -22°
- Wettest
- Jul
- 164 mm
- Driest
- Jan
- 11 mm
- Rain / yr
- 778 mm
- 117 wet days
- Daylight
- 9.0–15.0 h
- shortest–longest
- Elevation
- 709 m
- 41.4°N
- Clearest
- Oct
- 46% cloud
Hyesan is city in North Korea.
- Density
- 696/km²
- people per km²
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Hyesan 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 late May to late September.
Temperature through the year
Daily average highs and lows in Hyesan, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 4.6 months, from May 13 to September 28, with daily high temperatures above 16°C. The hottest month of the year in Hyesan is July, with an average high of 23°C and low of 14°C.
The cool season lasts 3.1 months, from November 26 to February 28, with daily high temperatures below -3°C. The coldest month of the year in Hyesan is January, with an average low of -22°C and high of -10°C.
Days typically run about 11°C warmer than nights, with the widest day–night swing (around 13°C) in February.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | -10 | -6 | 1 | 10 | 16 | 20 | 23 | 23 | 18 | 11 | 1 | -8 |
| Avg low (°C) | -22 | -19 | -11 | -2 | 5 | 10 | 14 | 14 | 7 | -1 | -10 | -20 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | -10 | -22 |
| Feb | -6 | -19 |
| Mar | 1 | -11 |
| Apr | 10 | -2 |
| May | 16 | 5 |
| Jun | 20 | 10 |
| Jul | 23 | 14 |
| Aug | 23 | 14 |
| Sep | 18 | 7 |
| Oct | 11 | -1 |
| Nov | 1 | -10 |
| Dec | -8 | -20 |
How hot and cold Hyesan 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 -28°C (around January 25), with roughly 213 freezing days a year (feels-like at or below 0°C) — 146 of them bitterly cold — worst in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | -10 | -6 | 1 | 9 | 16 | 20 | 23 | 23 | 18 | 11 | 0 | -8 |
| Air high (°C) | -10 | -6 | 1 | 10 | 16 | 20 | 23 | 23 | 18 | 11 | 1 | -8 |
| Feels-like low (°C) | -28 | -25 | -16 | -5 | 3 | 10 | 14 | 14 | 6 | -4 | -14 | -25 |
| Air low (°C) | -22 | -19 | -11 | -2 | 5 | 10 | 14 | 14 | 7 | -1 | -10 | -20 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | -10 | -10 | -28 | -22 |
| Feb | -6 | -6 | -25 | -19 |
| Mar | 1 | 1 | -16 | -11 |
| Apr | 9 | 10 | -5 | -2 |
| May | 16 | 16 | 3 | 5 |
| Jun | 20 | 20 | 10 | 10 |
| Jul | 23 | 23 | 14 | 14 |
| Aug | 23 | 23 | 14 | 14 |
| Sep | 18 | 18 | 6 | 7 |
| Oct | 11 | 11 | -4 | -1 |
| Nov | 0 | 1 | -14 | -10 |
| Dec | -8 | -8 | -25 | -20 |
Average hourly temperature in Hyesan
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 -22°C.
Hyesan 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 | -10° / -22° | 11 | 3.2 | 5 | 9.4 | 0.0 |
| Feb | -6° / -19° | 18 | 4.6 | 6.1 | 10.3 | 0.0 |
| Mar | 1° / -11° | 33 | 7.9 | 8.5 | 11.7 | 0.0 |
| Apr | 10° / -2° | 56 | 10.5 | 7.1 | 13.1 | 2.0 |
| May | 16° / 5° | 95 | 14.9 | 2 | 14.3 | 4.5 |
| Jun | 20° / 10° | 97 | 15.5 | 0 | 14.9 | 5.4 |
| Jul | 23° / 14° | 164 | 17.3 | 0 | 14.7 | 5.6 |
| Aug | 23° / 14° | 136 | 14.2 | 0 | 13.7 | 6.0 |
| Sep | 18° / 7° | 71 | 7.9 | 0.1 | 12.3 | 6.1 |
| Oct | 11° / -1° | 43 | 7.6 | 3 | 10.9 | 2.9 |
| Nov | 1° / -10° | 38 | 7.7 | 7.4 | 9.7 | 0.0 |
| Dec | -8° / -20° | 18 | 5.2 | 7 | 9.1 | 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.
Hyesan gets about 778 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 4.9 months, from around Apr 10 to Sep 6, peaking in July at about 57% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 21.
July is the wettest month by volume, with 164 mm over about 17 wet days; January is the driest, with 11 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 (%) | 11 | 16 | 26 | 35 | 47 | 51 | 55 | 46 | 27 | 23 | 26 | 17 |
| Rain days | 3 | 5 | 8 | 11 | 15 | 16 | 17 | 14 | 8 | 8 | 8 | 5 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 11 | 3 |
| Feb | 16 | 5 |
| Mar | 26 | 8 |
| Apr | 35 | 11 |
| May | 47 | 15 |
| Jun | 51 | 16 |
| Jul | 55 | 17 |
| Aug | 46 | 14 |
| Sep | 27 | 8 |
| Oct | 23 | 8 |
| Nov | 26 | 8 |
| Dec | 17 | 5 |
Monthly rainfall
Over a full year, Hyesan collects about 778 mm of rain across 117 wet days — roughly 65 mm in an average month.
It doesn’t fall evenly. July is the wettest month with 164 mm, while January is the driest at just 11 mm. The three wettest months alone bring about 51% 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) | 11 | 18 | 33 | 56 | 95 | 97 | 164 | 136 | 71 | 43 | 38 | 18 |
| Rain days | 3 | 5 | 8 | 11 | 15 | 16 | 17 | 14 | 8 | 8 | 8 | 5 |
| Snow days | 5 | 6 | 9 | 7 | 2 | 0 | 0 | 0 | 0 | 3 | 7 | 7 |
| Rainfall (mm) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 11 | 3 | 5 |
| Feb | 18 | 5 | 6 |
| Mar | 33 | 8 | 9 |
| Apr | 56 | 11 | 7 |
| May | 95 | 15 | 2 |
| Jun | 97 | 16 | 0 |
| Jul | 164 | 17 | 0 |
| Aug | 136 | 14 | 0 |
| Sep | 71 | 8 | 0 |
| Oct | 43 | 8 | 3 |
| Nov | 38 | 8 | 7 |
| Dec | 18 | 5 | 7 |
Snow in Hyesan
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.
Hyesan averages about 46 snowy days a year. Snow season runs roughly Sep 27 to May 27 — about 8 months.
March is snowiest, with roughly 8 days of snow and an estimated 32 cm of snowfall. Over the year that adds up to an estimated 177 cm of snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Snow days | 5 | 6 | 9 | 7 | 2 | 0 | 0 | 0 | 0 | 3 | 7 | 7 |
| Snowfall (cm) | 14 | 25 | 32 | 32 | 6 | 0 | 0 | 0 | 0 | 9 | 35 | 23 |
| Snow days | Snowfall (cm) | |
|---|---|---|
| Jan | 5 | 14 |
| Feb | 6 | 25 |
| Mar | 9 | 32 |
| Apr | 7 | 32 |
| May | 2 | 6 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 0 | 0 |
| Oct | 3 | 9 |
| Nov | 7 | 35 |
| Dec | 7 | 23 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Hyesan, 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 September 8 and lasts for 5.6 months, ending around February 25. The clearest month is October, when the sky is clear, mostly clear, or partly cloudy 61% of the time on average.
The cloudier part of the year begins around February 26 and lasts for 6.4 months, ending around September 7. The cloudiest month is July, when it is overcast or mostly cloudy 68% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 58 | 54 | 46 | 45 | 43 | 36 | 32 | 39 | 52 | 61 | 57 | 57 |
| Cloudier (%) | 42 | 46 | 54 | 55 | 57 | 64 | 68 | 61 | 48 | 39 | 43 | 43 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 58 | 42 |
| Feb | 54 | 46 |
| Mar | 46 | 54 |
| Apr | 45 | 55 |
| May | 43 | 57 |
| Jun | 36 | 64 |
| Jul | 32 | 68 |
| Aug | 39 | 61 |
| Sep | 52 | 48 |
| Oct | 61 | 39 |
| Nov | 57 | 43 |
| Dec | 57 | 43 |
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 14, brings about 15 hours of light; the shortest, around December 13, only 9 hours — a swing of roughly 6 hours.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 9.4 | 10.3 | 11.7 | 13.1 | 14.3 | 14.9 | 14.7 | 13.7 | 12.3 | 10.9 | 9.7 | 9.1 |
| Sunrise (AM) | 7:57 | 7:32 | 6:47 | 5:54 | 5:14 | 4:58 | 5:11 | 5:41 | 6:13 | 6:46 | 7:24 | 7:53 |
| Sunset (PM) | 5:16 | 5:52 | 6:27 | 7:01 | 7:33 | 7:57 | 7:54 | 7:22 | 6:30 | 5:38 | 5:02 | 4:54 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 9.4 | 7:57 | 5:16 |
| Feb | 10.3 | 7:32 | 5:52 |
| Mar | 11.7 | 6:47 | 6:27 |
| Apr | 13.1 | 5:54 | 7:01 |
| May | 14.3 | 5:14 | 7:33 |
| Jun | 14.9 | 4:58 | 7:57 |
| Jul | 14.7 | 5:11 | 7:54 |
| Aug | 13.7 | 5:41 | 7:22 |
| Sep | 12.3 | 6:13 | 6:30 |
| Oct | 10.9 | 6:46 | 5:38 |
| Nov | 9.7 | 7:24 | 5:02 |
| Dec | 9.1 | 7:53 | 4:54 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Hyesan averages about 10 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 4 and 15 days.
The sunnier stretch runs 5.7 months, from around Sep 12 to Mar 4. The sunniest month is October, with roughly 14 sunny days (mixed).
The greyest month is July, down near 4 sunny days — about 73% fewer than the October peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 14 | 11 | 9 | 8 | 7 | 5 | 4 | 6 | 10 | 15 | 12 | 13 |
| Sky | Mixed | Mixed | Mixed | Mixed | Gloomy | Gloomy | Gloomy | Gloomy | Mixed | Mixed | Mixed | Mixed |
| Sunny days | Sky | |
|---|---|---|
| Jan | 14 | Mixed |
| Feb | 11 | Mixed |
| Mar | 9 | Mixed |
| Apr | 8 | Mixed |
| May | 7 | Gloomy |
| Jun | 5 | Gloomy |
| Jul | 4 | Gloomy |
| Aug | 6 | Gloomy |
| Sep | 10 | Mixed |
| Oct | 15 | Mixed |
| Nov | 12 | Mixed |
| Dec | 13 | Mixed |
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 Hyesan, how humid it feels changes dramatically over the year.
The more humid part of the year lasts 2.2 months, from around June 28 to September 2. The muggiest month is August, when the air feels humid, muggy or worse about 39% of the time.
The most comfortable stretch runs from around September 3 to June 27, 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 | 100 | 80 | 19 | 30 | 91 | 100 | 100 | 100 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 0 | 18 | 42 | 32 | 7 | 0 | 0 | 0 |
| Humid (%) | 0 | 0 | 0 | 0 | 0 | 2 | 32 | 32 | 2 | 0 | 0 | 0 |
| Muggy (%) | 0 | 0 | 0 | 0 | 0 | 0 | 7 | 7 | 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 | 80 | 18 | 2 | 0 |
| Jul | 19 | 42 | 32 | 7 |
| Aug | 30 | 32 | 32 | 7 |
| Sep | 91 | 7 | 2 | 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 Hyesan is typically calm, near 7 km/h, and varies little with the seasons.
The windier part of the year lasts 3.9 months, from around Feb 2 to Jun 1. The windiest month is March, averaging about 9 km/h (calm).
The calmer part of the year runs from around Jun 2 to Oct 16, with August the calmest month at about 6 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 7 | 8 | 9 | 9 | 8 | 6 | 6 | 6 | 6 | 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 | 9 | calm |
| May | 8 | calm |
| Jun | 6 | calm |
| Jul | 6 | calm |
| Aug | 6 | calm |
| Sep | 6 | calm |
| Oct | 7 | calm |
| Nov | 7 | calm |
| Dec | 7 | calm |
Hazard calendar for Hyesan
When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.
Hyesan's rainy season runs May–August, when most of the year's rain falls.
Best time to visit Hyesan
To characterize how pleasant the weather is in Hyesan throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around early June, Hyesan 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 Hyesan for general outdoor tourist activities is from late May to late September, with a peak score in the first week of September.
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 | 2.0 | 4.5 | 5.4 | 5.6 | 6.0 | 6.0 | 2.9 | 0.1 | 0.0 |
| Rating | poor | poor | poor | poor | fair | fair | good | good | good | poor | poor | poor |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 0.0 | poor |
| Feb | 0.0 | poor |
| Mar | 0.0 | poor |
| Apr | 2.0 | poor |
| May | 4.5 | fair |
| Jun | 5.4 | fair |
| Jul | 5.6 | good |
| Aug | 6.0 | good |
| Sep | 6.0 | good |
| Oct | 2.9 | poor |
| Nov | 0.1 | 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 Hyesan for hot-weather activities is from early July to late August, with a peak score in the first 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 Hyesan, 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 -10°C), pack a warm layer and a heavy coat.
In July, Hyesan sees daytime highs around 23°C and nights near 14°C. Pack rain gear. Worth having: light clothes and sun protection. About 17 days see rain.
UV index (midday) in Hyesan 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 Hyesan peaks around August 18 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 1 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 8 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 2 | 4 | 6 | 7 | 7 | 6 | 9 | 7 | 4 | 2 | 1 |
| Level | Low | Moderate | Moderate | High | Very high | Very high | High | Very high | Very high | Moderate | Moderate | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Low |
| Feb | 2 | Moderate |
| Mar | 4 | Moderate |
| Apr | 6 | High |
| May | 7 | Very high |
| Jun | 7 | Very high |
| Jul | 6 | High |
| Aug | 9 | Very high |
| Sep | 7 | Very high |
| Oct | 4 | Moderate |
| Nov | 2 | Moderate |
| Dec | 1 | Low |
Average hourly UV index in Hyesan
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 August the burn window is concentrated in the middle of the day: about 8 hours a day reach index 3 (protection recommended), and 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 | 4 | 6.5 | 7.5 | 8 | 7 | 8 | 6.5 | 4 | 0 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 0 | 3.5 | 4 | 2.5 | 5 | 3 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 4 | 0 |
| Apr | 6.5 | 0 |
| May | 7.5 | 3.5 |
| Jun | 8 | 4 |
| Jul | 7 | 2.5 |
| Aug | 8 | 5 |
| Sep | 6.5 | 3 |
| Oct | 4 | 0 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Air quality in Hyesan 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 Hyesan is worst in March — around 36 µg/m³ PM2.5 (poor), about 2.4× the cleanest month (August, 15 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) | 28 | 29 | 36 | 34 | 29 | 22 | 18 | 15 | 18 | 26 | 23 | 25 |
| Level | Moderate | Moderate | Poor | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 28 | Moderate |
| Feb | 29 | Moderate |
| Mar | 36 | Poor |
| Apr | 34 | Moderate |
| May | 29 | Moderate |
| Jun | 22 | Moderate |
| Jul | 18 | Moderate |
| Aug | 15 | Moderate |
| Sep | 18 | Moderate |
| Oct | 26 | Moderate |
| Nov | 23 | Moderate |
| Dec | 25 | Moderate |
Growing season
The growing season in Hyesan typically lasts about 172 days, from around April 23 to October 11 — the span where a frost-free day is more likely than not. It is reliably frost-free from May 11 to September 23.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 0 | 0 | 3 | 35 | 91 | 100 | 100 | 100 | 94 | 41 | 5 | 0 |
| Frost nights | 31 | 28 | 31 | 30 | 10 | 0 | 0 | 0 | 6 | 31 | 30 | 31 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 0 | 31 |
| Feb | 0 | 28 |
| Mar | 3 | 31 |
| Apr | 35 | 30 |
| May | 91 | 10 |
| Jun | 100 | 0 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 94 | 6 |
| Oct | 41 | 31 |
| Nov | 5 | 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. Hyesan banks about 781 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 | 26 | 156 | 270 | 254 | 74 | 0 | 0 | 0 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 0 |
| Feb | 0 |
| Mar | 0 |
| Apr | 0 |
| May | 26 |
| Jun | 156 |
| Jul | 270 |
| Aug | 254 |
| Sep | 74 |
| 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.
Hyesan receives about 4.2 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.2 and 5.8 kWh/m².
The brighter stretch of the year lasts 7.0 months, from around Mar 1 to Sep 28. The brightest month is June, averaging about 5.6 kWh/m² (bright).
The dimmest month is December, down near 2.2 kWh/m² — roughly 60% less than the June peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 2.7 | 3.6 | 4.9 | 5.5 | 5.7 | 5.6 | 4.9 | 4.7 | 4.5 | 3.6 | 2.5 | 2.2 |
| Level | Moderate | Moderate | Bright | Bright | Bright | Bright | Bright | Bright | Bright | Moderate | Moderate | Moderate |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 2.7 | Moderate |
| Feb | 3.6 | Moderate |
| Mar | 4.9 | Bright |
| Apr | 5.5 | Bright |
| May | 5.7 | Bright |
| Jun | 5.6 | Bright |
| Jul | 4.9 | Bright |
| Aug | 4.7 | Bright |
| Sep | 4.5 | Bright |
| Oct | 3.6 | Moderate |
| Nov | 2.5 | Moderate |
| Dec | 2.2 | Moderate |
Where is Hyesan?
Hyesan sits at 41.4°N, 128.2°E, 709 m above sea level, in North Korea. The nearest listed city is Hyesan-dong, 1.0 km away.
Topography around Hyesan
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Hyesan.
Within 3 km, the terrain around Hyesan has significant variations in elevation — a maximum elevation change of 366 m around an average of 790 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 990 m; within 80 km, very significant variations in elevation — a maximum elevation change of 2,277 m.
The land around Hyesan is covered by cropland (33%), artificial surfaces (27%) and trees (22%) within 3 km, trees (48%) and grassland (28%) within 16 km, and trees (85%) within 80 km.
North Korea travel facts
- Travel advisory
- Level 4
- Do Not Travel
- Power plugs
- Type C / F
- 220 V · 50 Hz
- Safe drinking water
- 67%
- of population, 2023
- Road deaths
- 24.2
- per 100k/yr, 2019
- Income group
- Low
- World Bank
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 Hyesan (41.4017°, 128.1778°, elevation 709 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).