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Geoje weather by month: averages, rainfall & climate trends

Geoje swings through a wide annual range, with 20.4°C between the monthly means of its warmest and coldest months. The heavier rain months run from April to September. Geoje weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+1.7°Chigh above average

21° / 14°Today
19° / 16°Average
see today in detail →

How it's changed

+1.3°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4911frost days a year now (2016–2025) · 19 in the 1940sfrost days a year · 19 in the 1940s60days above 25°C a year now (2016–2025) · 39 in the 1940sdays above 25°C · 39 in the 1940s+1.3°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 45 mmhigh 7°low 3°February, rain 59 mmhigh 8°low 4°March, rain 94 mmhigh 11°low 7°April, rain 135 mmhigh 14°low 12°May, rain 137 mmhigh 17°low 15°June, rain 204 mmhigh 20°low 19°July, rain 228 mmhigh 24°low 23°August, rain 167 mmhigh 26°low 25°September, rain 172 mmhigh 24°low 22°October, rain 78 mmhigh 20°low 17°November, rain 64 mmhigh 15°low 11°December, rain 39 mmhigh 10°low 6°wettest month July, 228 mm · 1,421 mm a yearsee month by month →

Right now

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

Right now

17.0°

14°feels like
57%humidity
8°dew point
20 km/hfrom NW
UV index0.0
sunrise06:35sunset17:43day length11h 08m
TodayOvercast21°14°
ThuClear16°11°
FriOvercast20°16°
SatLight rain19°17°
SunOvercast22°19°
MonRain22°21°
TueClear22°12°

On this date: October 21

Today (forecast)
21° / 14°
Average for October 21
19° / 16°

High above average · +1.7°C

  • Highest since 1940: 22.8° · 2024
  • Lowest since 1940: 10.4° · 1979
  • One year ago: 20° / 18°

Every October 21 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 21 on record (n = 86). 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 Geoje is sampled from the ECMWF ERA5 reanalysis at 34.81°N, 128.71°E, with daily records since 1940.

Coordinates
34.81°N, 128.71°E
Time zone
Asia/Seoul
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

27 of the last 30 days were warmer than the historical average for that date. Average difference: +2.0°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 26.3°C and nights around 25.0°C. Around 110 nights a year stay above 20°C. In January, the coolest month, afternoons reach about 7.2°C and nights dip to 3.0°C. Around 11 days a year dip below freezing.

Geoje picks up roughly 1,421 mm a year, with a peak of 228 mm in July and as little as 39 mm in December.

The record here starts in 1940, and since then the annual mean in Geoje has climbed 1.3°C from the first ten years to the last ten. Days above 25°C have grown noticeably more frequent, from around 40 a year in the first decade to about 60 in the last.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 20°C. Wettest month: July (~228 mm). Whole year averages ~1,421 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 83 rainy days a year: most in July (~11), fewest in December (~4).

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.

Geoje 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
January7.2°3.0°45 mm49.9 h17.6° (2020)−6.8° (1967)
February8.1°4.0°59 mm510.7 h16.5° (2009)−6.7° (1957)
March10.9°7.3°94 mm711.7 h17.2° (1979)−3.4° (1951)
April14.1°11.7°135 mm812.9 h18.9° (1999)2.4° (1972)
May17.1°15.4°137 mm713.8 h22.3° (1979)10.2° (1947)
June20.1°18.9°204 mm914.3 h24.3° (1994)14.2° (1981)
July24.0°22.9°228 mm1114.1 h29.4° (2018)17.5° (1986)
August26.3°25.0°167 mm1013.3 h30.1° (2017)19.5° (1950)
September23.9°22.0°172 mm912.2 h29.4° (2024)14.5° (1987)
October19.7°16.9°78 mm511.1 h25.2° (2024)6.3° (1974)
November14.8°11.2°64 mm510.1 h21.8° (2023)−0.3° (1970)
December9.7°5.6°39 mm49.7 h18.7° (1953)−4.4° (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 +1.3°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: +0.12°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: +0.15°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 ≥ 25°C per year: 39.1 early in the record → 60.0 recently. Frost days: 19 → 11.

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 2017, coldest in 1967: 30.1°C / −6.8°C.

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

Annual rainfall

~1,421 mm/year on average. Last decade: +4% vs that average. Long-term trend: +25 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 Geoje

Which is the warmest month in Geoje?
On long-term average, the warmest month in Geoje is August (mean daily temperature of about 25.7°C) and the coolest is January (about 5.3°C).
How does today's temperature in Geoje compare to the historical average?
On October 21, 2026, Geoje is forecast to reach a high of 20.8°C and a low of 13.6°C. The long-term average for this date (the full record since 1940) is a high of 19.1°C and a low of 16.3°C, so today's high is 1.7°C warmer than that average.
How much has Geoje warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Geoje is about 1.3°C warmer.
How much does it rain in Geoje?
Geoje receives about 1,421 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Geoje?
Over the full record (since 1940), the annual mean temperature in Geoje is about 15.2°C. The warmest month is August and the coolest is January.
What are the average temperatures in Geoje by month?
Average daily highs and lows for each month in Geoje (°C, full record since 1940): January 7°/3°, February 8°/4°, March 11°/7°, April 14°/12°, May 17°/15°, June 20°/19°, July 24°/23°, August 26°/25°, September 24°/22°, October 20°/17°, November 15°/11°, December 10°/6°.
What is the weather like in Geoje in summer?
Summer in Geoje (June to August) is wet and pleasantly warm. It warms from 20°C by day and 19°C at night in June to 26°C and 25°C in August. Rain is steady at around 200 mm a month, spread over roughly 10 days. No season is wetter.
What is the weather like in Geoje in winter?
Winter in Geoje (December to February) is on the cool side. Afternoons run 7–10°C and nights 3–6°C; January is the coldest month. Rain picks up through the season: 4 rainy days and 39 mm in December, 5 days and 59 mm in February. It is the driest season of the year.
What is the weather like in Geoje in spring?
Spring in Geoje (March to May) is wet and cool. It warms from 11°C by day and 7°C at night in March to 17°C and 15°C in May. Rain is steady at around 122 mm a month, spread over roughly 7 days.
What is the weather like in Geoje in autumn?
Autumn in Geoje (September to November) is wet and mild. September still brings 24°C afternoons and 22°C nights, November only 15°C and 11°C. Rain falls off from 172 mm on 9 days in September to 64 mm on 5 days in November.
How many days a year does it rain in Geoje?
On long-term average, Geoje has about 83 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,421 mm.

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