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Yangsan weather by month: averages, rainfall & climate trends

Yangsan swings through a wide annual range, with 24.2°C between the monthly means of its warmest and coldest months. Rainfall leans toward the stretch from April to September. Yangsan weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

−1.7°Chigh below average

19° / 17°Today
21° / 13°Average
see today in detail →

How it's changed

+2.6°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4943frost days a year now (2016–2025) · 70 in the 1940sfrost days a year · 70 in the 1940s44days above 30°C a year now (2016–2025) · 11 in the 1940sdays above 30°C · 11 in the 1940s+2.6°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 31 mmhigh 7°low −1°February, rain 45 mmhigh 9°low 0°March, rain 77 mmhigh 13°low 4°April, rain 118 mmhigh 18°low 9°May, rain 121 mmhigh 23°low 14°June, rain 183 mmhigh 25°low 18°July, rain 234 mmhigh 28°low 23°August, rain 182 mmhigh 30°low 24°September, rain 166 mmhigh 26°low 19°October, rain 67 mmhigh 21°low 13°November, rain 51 mmhigh 15°low 7°December, rain 27 mmhigh 9°low 1°wettest month July, 234 mm · 1,302 mm a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Rain

Right now

18.6°

21°feels like
96%humidity
18°dew point
3 km/hfrom N
UV index0.0
sunrise06:34sunset17:43day length11h 09m
TueLight rain19°17°
WedPartly cloudy19°10°
ThuClear17°6°
FriOvercast20°14°
SatLight rain20°17°
SunLight rain21°19°
MonRain21°19°

On this date: October 19

Today (forecast)
19° / 17°
Average for October 19
21° / 13°

High below average · −1.7°C

  • Highest since 1940: 27.2° · 1961
  • Lowest since 1940: 7.0° · 1956
  • One year ago: 21° / 15°

Every October 19 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 19 on record (n = 87). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Yangsan is sampled from the ECMWF ERA5 reanalysis at 35.34°N, 129.03°E, with daily records since 1940.

Coordinates
35.34°N, 129.03°E
Time zone
Asia/Seoul
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

25 of the last 31 days were warmer than the historical average for that date. Average difference: +1.9°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

August brings the year's peak warmth, with afternoons typically reaching 29.7°C and nights around 24.0°C. Around 100 nights a year stay above 20°C. In January, the coolest month, afternoons reach about 6.8°C and nights dip to −1.2°C. Around 45 days a year dip below freezing.

The yearly total for Yangsan comes to about 1,302 mm; monthly amounts range from 27 mm in December up to 234 mm in July.

Over the full record (since 1940), the annual mean temperature in Yangsan has risen by 2.6°C between its first decade and its last. The count of days past 30°C has risen from roughly 11 a year to 45 between the record's first and last decades.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 24°C. Wettest month: July (~234 mm). Whole year averages ~1,302 mm of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 78 rainy days a year: most in July (~12), fewest in December (~3).

Bars = average number of days with ≥ 2 mm per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Yangsan month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January6.8°−1.2°31 mm39.9 h17.4° (1960)−13.5° (1967)
February8.8°0.5°45 mm410.7 h22.1° (2021)−11.3° (1957)
March13.1°4.4°77 mm611.7 h25.6° (2001)−7.5° (1977)
April18.3°9.4°118 mm712.9 h28.8° (1999)−1.9° (1972)
May22.5°13.9°121 mm713.9 h34.1° (2000)6.0° (1953)
June25.2°18.4°183 mm914.4 h33.5° (2024)10.3° (1981)
July28.3°23.1°234 mm1214.2 h36.6° (1994)15.6° (1993)
August29.7°24.0°182 mm1113.3 h37.4° (2013)14.0° (1972)
September26.1°19.5°166 mm912.2 h35.2° (1994)9.1° (1956)
October21.5°13.0°67 mm411.1 h29.6° (2021)1.6° (1986)
November15.4°6.7°51 mm410.1 h26.3° (1979)−4.7° (1966)
December9.1°0.7°27 mm39.6 h21.0° (1953)−10.4° (1976)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +2.6°C.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.31°C per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Dec–Feb is warming fastest: +0.36°C per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 30°C per year: 10.5 early in the record → 44.2 recently. Frost days: 70 → 43.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2013, coldest in 1967: 37.4°C / −13.5°C.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~1,302 mm/year on average. Last decade: +6% vs that average. Long-term trend: +27 mm per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Yangsan

Which is the warmest month in Yangsan?
On long-term average, the warmest month in Yangsan is August (mean daily temperature of about 26.7°C) and the coolest is January (about 2.5°C).
How does today's temperature in Yangsan compare to the historical average?
On October 19, 2026, Yangsan is forecast to reach a high of 19.4°C and a low of 16.7°C. The long-term average for this date (the full record since 1940) is a high of 21.1°C and a low of 12.7°C, so today's high is 1.7°C cooler than that average.
How much has Yangsan warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Yangsan is about 2.6°C warmer.
How much does it rain in Yangsan?
Yangsan receives about 1,302 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Yangsan?
Over the full record (since 1940), the annual mean temperature in Yangsan is about 14.7°C. The warmest month is August and the coolest is January.
What are the average temperatures in Yangsan by month?
Average daily highs and lows for each month in Yangsan (°C, full record since 1940): January 7°/−1°, February 9°/0°, March 13°/4°, April 18°/9°, May 23°/14°, June 25°/18°, July 28°/23°, August 30°/24°, September 26°/19°, October 21°/13°, November 15°/7°, December 9°/1°.
What is the weather like in Yangsan in summer?
Summer in Yangsan (June to August) is wet and warm. June starts at 25°C by day and 18°C at night; by August it is 30°C and 24°C. Rain falls on about 11 days a month, adding up to around 200 mm. No season is wetter.
What is the weather like in Yangsan in winter?
December to February is winter in Yangsan, and it is on the cool side. Daytime highs sit at 7–9°C and nights at −1 to 1°C; January is the coldest month. Rain rises from 27 mm on 3 days in December to 45 mm on 4 days in February. It is the driest season of the year.
What is the weather like in Yangsan in spring?
In spring, March through May, Yangsan is wet and fairly mild. March is still 13°C in the afternoon and 4°C at night, May already 23°C and 14°C. Rain picks up through the season: 6 rainy days and 77 mm in March, 7 days and 121 mm in May.
What is the weather like in Yangsan in autumn?
Autumn in Yangsan (September to November) is mild. September still brings 26°C afternoons and 19°C nights, November only 15°C and 7°C. Rain eases through the season: 9 rainy days and 166 mm in September, 4 days and 51 mm in November.
How many days a year does it rain in Yangsan?
On long-term average, Yangsan has about 78 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,302 mm.

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