WEATHERblaze

Okayama Historical Weather Data & Climate

Historical Climate Data for 26 Cities
1981–2025
Japan

Quick Climate Facts

(19812025)
Hottest City
🔥
Katsuyama
Jul High 32.4°C
Coldest City
❄️
Katsuyama
Jan Low -6.6°C
Wettest City
🌧
Misaki
1769 mm/yr
Driest City
🏜️
Satoshō
1383 mm/yr
Hottest Month
🌡
August
Avg 25.9°C
Max 32.9°C
Coldest Month
🧊
January
Avg 4.6°C
Min -3.7°C
Cities With Data
🏙️
26
cities in Okayama
Data Coverage
📅
45 yrs
19812025

Okayama Climate Overview

Okayama has a warm temperate climate with warm summers and cold winters.

Okayama has an average annual temperature of 14.6°C across all 26 cities, with approximately 1421 mm of annual precipitation and average humidity of 81%. Temperatures peak in August and drop to their lowest in January, while rainfall is highest during summer months.

The warmest city is Katsuyama with average July highs of 32.4°C, while Katsuyama is the coldest with average January lows of -6.6°C. Humidity remains high throughout the year creating cold and damp conditions. These seasonal patterns make summer pleasant for travel, while winters can bring frost and occasional snowfall.

🏙️ Cities in Okayama — Weather History

📊 Okayama Monthly Climate Data

Monthly Climate Data
Month🌤️HighLowAvgHumid %Rain (mm)Wind (m/s)Solar (kWh/m²)
January🌤️12.8°C-3.7°C4.6°C82%702.72.10
February🌤️14.8°C-3.5°C5.6°C80%732.72.80
March18.5°C-2.0°C8.2°C78%1022.63.80
April23.3°C0.7°C12.0°C77%1092.24.90
May26.6°C6.5°C16.5°C78%1331.95.30
June🌧️29.3°C11.9°C20.6°C82%1831.64.90
July🌧️32.1°C17.7°C24.9°C84%1921.65.00
August32.9°C19.0°C25.9°C82%1221.75.20
September🌧️30.8°C13.6°C22.2°C82%1762.04.00
October25.9°C6.8°C16.3°C80%1112.13.40
November🌤️21.1°C1.7°C11.4°C81%792.22.50
December🌤️15.9°C-1.8°C7.1°C82%712.52.00

Showing average climate conditions across 45 years (1981–2025) · averaged across all 26 cities in Okayama

🌦 Weather in Okayama Across Seasons

❄️ Winter in Okayama

January is Okayama's coldest month, with average lows reaching -3.7°C.
🌡️December to February (avg) · -3.0°C14.5°C

🧥 Expect frosty nights and below-freezing temperatures during this Cold Winter period.

☀️ Summer in Okayama

Summer temperatures in Okayama peak in August, climbing to 32.9°C.
🌡️July to September (avg) · 16.8°C31.9°C

🌤️ Early mornings and evenings are most comfortable during this Hot Summer season.

🌧️ Rainy Season in Okayama

Okayama sees its highest rainfall in July, receiving approximately 192 mm of precipitation.
🌧️June to September (avg) ·  up to 192 mm

☔ Heavy Rainfall expected — carry rain gear and plan outdoor activities around these months.

📈 Okayama Monthly Averages

🌡️ Temperature Patterns

Region-wide monthly averages across 26 cities · 19812025 · °C

🌡️ Okayama Monthly Temperature Guide

August is the hottest month in Okayama, with average highs reaching 32.9°C, while January is the coldest with lows dropping to -3.7°C.

Temperatures rise steadily from spring, peak in August, and gradually decline through autumn into winter.

These seasonal patterns make summer pleasant for travel, while winters can bring frost and occasional snowfall.

🌧️ Rainfall Distribution

Region-wide monthly rainfall · 19812025 · mm/month

💨 Humidity & Wind Speed

Monthly averages · 19812025

🌧 Rainfall & Humidity in Okayama

Okayama receives its highest rainfall in July, while humidity peaks during summer months.
🌧️ Wettest: July192 mm☀️ Driest: January70 mm

💧 Humidity peaks at 84% in July · annual avg 81%

📅 Okayama Yearly Climate Trends

The warmest year on record was 2024 (avg: 16.0°C), while the coldest year was 1986 (avg: 13.4°C).

📊 Key Climate Trends

  • 🌡️ Okayama's temperature shows a slight warming trend over the past decade
  • 📈 Minimum temperatures show a slight warming trend in recent years
  • 🌧️ Rainfall varies year-to-year without a clear long-term trend

🌡️ Annual Temperature Trend

View Range:

Averaged across all 26 cities in Okayama · Last 10 years · °C

Okayama's temperature shows a slight warming trend over the past decade. The region-wide average sits at 14.6°C with annual rainfall averaging 1421 mm.

🌧️ Annual Precipitation

View Range:

Averaged across all 26 cities in Okayama · Last 10 years · mm/year

Annual rainfall in Okayama shows noticeable variation. Rainfall varies year-to-year without a clear long-term trend.
📅 Yearly Climate Data Overview

🔥 hottest  ·  ❄️ coldest  ·  🌧️ wettest

ℹ️ Values are averages across all 26 cities in Okayama for each year.

YearMin TempAvg TempMax TempRainfall (mm)Avg HumidityAvg Wind
2025
6.4°C15.5°C24.6°C151581%2.0 m/s
2024
7.4°C16.0°C24.5°C189283%2.1 m/s
2023 🔥
6.8°C15.9°C24.9°C180181%2.0 m/s
2022
6.0°C15.0°C24.0°C114779%2.0 m/s
2021
6.3°C15.0°C23.6°C176582%2.1 m/s
2020
6.5°C15.0°C23.4°C164881%2.1 m/s
2019
6.2°C15.1°C24.0°C127581%2.0 m/s
2018 🌧️
5.4°C15.0°C24.6°C189382%2.1 m/s
2017
5.5°C14.3°C23.1°C159181%2.1 m/s
2016
5.8°C14.9°C24.0°C175182%2.0 m/s

Showing 1 to 10 of 45 years

🏙️ Explore More Cities in Okayama

❓ Frequently Asked Questions

What is the hottest city in Okayama?
Katsuyama is the hottest city in Okayama with an average July high of 32.4°C based on 45 years of data. View Katsuyama weather history →
What is the coldest city in Okayama?
Katsuyama is the coldest city with average January lows of -6.6°C. View Katsuyama weather history →
Which city in Okayama gets the most rain?
Misaki is the wettest city in Okayama with approximately 1769 mm of annual precipitation on average.
What is the warmest month in Okayama?
August is the warmest month in Okayama, with region-wide average highs of 32.9°C and average lows of 19.0°C.
What is the coldest month in Okayama?
January is the coldest month in Okayama with average lows of -3.7°C and average highs of 12.8°C.
What is the rainiest month in Okayama?
July is the rainiest month in Okayama with approximately 192 mm on average, while January is the driest with 70 mm.
How many cities in Okayama have weather data?
WeatherBlaze has historical weather data for 26 cities in Okayama, covering 45 years of climate records from 1981 to 2025.
Where does this climate data come from?
All data is sourced from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis data. It includes monthly temperature, precipitation, humidity, wind speed, and solar radiation.

📡 Data Source

All weather data is sourced from NASA POWER (Prediction of Worldwide Energy Resources), a NASA project providing solar and meteorological data for renewable energy, building efficiency, and agricultural research.

Parameters included:
  • Temperature (Min, Max)
  • Precipitation
  • Relative Humidity
  • Wind Speed
  • Solar Radiation
Data specifications:
  • Resolution: Monthly
  • Spatial: 0.5° × 0.625°
  • Source: MERRA-2
  • Coverage: 19812025
  • Cities: 26 in Okayama