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Okayama weather history

Live conditions, the day's high and low compared with the long-term normal, monthly climate averages, all-time records and the city's warming trend since 1940 — all on one page for Okayama, Japan.

Today

26°/19°

Normal for this date 25° / 17°

About normal+0.3°C

How it’s changed

+2.8°Caverage temperature, 2016–2025 vs 1940–1949
20frost days a year now (2016–2025) · 62 in the 1940s
67days above 30°C a year now · 16 in the 1940s

Right now

What it's doing today vs the historical normal for this date.
Overcast

Right now

20.1°

23°feels like
91%humidity
19°dew point
4 km/hfrom NE
sunrise04:51sunset19:14day length14h 23m
SatOvercast26°19°
SunRain22°20°
MonOvercast27°20°
TueLight rain22°18°
WedPartly cloudy26°18°
ThuOvercast27°16°
FriOvercast26°17°

On this date — June 5

Today (forecast)
26° / 19°
Normal for June 5
25° / 17°

About average

  • Record high: 33.1° · 2002
  • Record low: 9.1° · 1948
  • One year ago: 28.3°

Every June 5 in history — coldest to hottest

Daily highsDaily lows

Dots show daily highs (top) and lows (bottom) for each June 5 on record (n = 86). Outlined dots are today's forecast.

Next 24 hours

NowOvercast20°
01Overcast20°
02Overcast20°
03Overcast20°
04Overcast20°
05Showers19°
06Overcast20°
07Overcast21°
08Overcast21°
09Overcast22°
10Overcast23°
11Overcast24°
12Overcast25°
13Overcast26°
14Overcast26°
15Overcast25°
16Overcast25°

Last 30 days

20 of the last 24 days were warmer than the historical normal for that date. Average difference: +1.8°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above normal; 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. Normal = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

Climate

What a typical year looks like — built from the full record.

Climate overview

The warmest month of the year in Okayama is August, with a daily mean around 27.8°C and typical afternoon highs of 31.6°C. The coolest is January, when daily means drop to roughly 4.7°C and overnight lows hover around 1.0°C. Between the two extremes the climate moves through a fairly predictable seasonal cycle that you can see in the monthly chart below.

Total annual precipitation in Okayama averages about 1308 mm. The wettest month is usually June with around 192 mm of rain, while December is the driest at roughly 37 mm. The split between wet and dry seasons gives a quick sense of when umbrellas and waterproof shoes are most useful.

Over the full record (since 1940), the annual mean temperature in Okayama has shifted by +2.8°C between the first decade and the last. The hottest single day in the record reached 39.2°C in 2001; the coldest, -7.9°C in 1981.

Monthly temperature range

August is the warmest month, January the coolest — a yearly swing of 23°C.

Each bar is the average daily low → average daily high for that month. Color shifts cool→warm by month temperature. The dot is the monthly mean. Normal = each month's value averaged across every year of record (1940–2026).

Monthly rainfall

Wettest month: June (~192 mm). Whole year averages ~1308 mm of rain.

Average total millimetres of rainfall in each calendar month, across the full record.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre — a measured proxy for how sunny the month is.

Monthly reference table

Numerical reference: average highs/lows, mean rainfall, and absolute records for each month of the year. Normal = each month's value averaged across every year of record (1940–2026).

MonthAvg highAvg lowRainRecord highRecord low
January9.0°1.0°40 mm17.9° (1969)-7.9° (1981)
February9.7°1.4°54 mm22.4° (2004)-6.9° (1978)
March13.3°4.2°87 mm24.4° (1979)-4.1° (1984)
April18.8°9.7°113 mm30.0° (2005)-1.8° (1962)
May23.0°14.5°128 mm33.8° (2000)3.4° (1953)
June26.2°19.1°192 mm35.5° (2005)7.3° (1969)
July30.0°23.5°189 mm38.8° (1994)12.8° (1966)
August31.6°24.3°125 mm39.2° (2001)14.3° (1956)
September27.9°20.1°175 mm37.7° (2025)7.9° (1987)
October22.3°13.1°105 mm32.0° (2018)2.5° (1986)
November16.8°7.6°63 mm26.8° (2023)-3.2° (1981)
December11.4°2.8°37 mm20.4° (2018)-7.7° (1981)

How it has changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +2.8°C.

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

Hot days vs frost days

Days ≥ 30°C per year: 15.9 early in the record → 66.8 recently. Frost days: 62 → 20.

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. Normal = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

All-time high in 2001, all-time low in 1981: 39.2°C / -7.9°C.

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

Annual rainfall

~1308 mm/year on average. Last decade ran +9% vs that average.

One bar per year of total rainfall. Dashed line is the long-term average. Normal = 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 — ~30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical normal 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). Normal = the long-term average for that calendar date (1940–2026).

Okayama — Frequently asked questions

Which is the warmest month in Okayama?
On long-term average, the warmest month in Okayama is August (mean about 27.8°C) and the coolest is January (about 4.7°C).
How does today's temperature in Okayama compare to the historical average?
On 2026-06-05, Okayama is forecast to reach a high of 25.6°C and a low of 19.4°C. The long-term normal for this date (1991–2020 average) is a high of 25.3°C and a low of 16.9°C — today's high is about equal to the historical normal.
How much has Okayama warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Okayama is about 2.8°C warmer.
How much does it rain in Okayama?
Okayama receives about 1308 mm of precipitation per year on long-term average, with June typically the wettest month.