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Yokohama weather by month — averages, rainfall & climate trends

Average temperatures and rainfall by month, a climate graph, today's conditions versus the long-term average, and how the climate has shifted since 1940 — all on one page for Yokohama, Japan.

Right now

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

Right now

26.7°

33°feels like
87%humidity
24°dew point
4 km/hfrom S
sunrise04:41sunset18:54day length14h 14m
MonClear35°26°
TueOvercast36°27°
WedPartly cloudy36°28°
ThuPartly cloudy35°28°
FriPartly cloudy34°27°
SatPartly cloudy35°27°
SunOvercast31°25°

On this date — July 19

Today (forecast)
35° / 26°
Average for July 19
27° / 23°

Warmer than usual · 8.0°C above the average high

  • Record high: 31.0° · 1990
  • Record low: 18.8° · 1976
  • One year ago: 29.4°

Every July 19 in history — coldest to hottest

Daily highsDaily lows

Dots show daily highs (top) and lows (bottom) for each July 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 Yokohama is sampled from the ECMWF ERA5 reanalysis at 35.43°N, 139.65°E, with daily records since 1940.

Coordinates
35.43°N, 139.65°E
Time zone
Asia/Tokyo
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

22 of the last 31 days were warmer than the historical average for that date. Average difference: +1.3°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 — 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 — what a typical year looks like, from the full record.

Climate overview

Yokohama swings through a wide annual range, with 20.6°C between the monthly means of its warmest and coldest months. August brings the year's peak warmth: daily means of 26.3°C, with afternoons typically reaching 28.5°C. Around 115 nights a year stay above 20°C. At the other extreme, January averages 5.7°C, with typical overnight lows of 2.8°C.

The heavier rain months run from May to July. The yearly total for Yokohama comes to about 1447 mm; monthly amounts range from 59 mm in December up to 188 mm in October.

The record here starts in 1940, and since then the annual mean in Yokohama has climbed 2.0°C from the first ten years to the last ten. Days above 30°C have grown noticeably more frequent — from around 3 a year in the first decade to about 30 in the last.

Climate graph (climograph)

August is the warmest month, January the coolest — a yearly swing of 21°C. Wettest month: October (~188 mm). Whole year averages ~1447 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).

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.

Yokohama 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. Record high/low are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainDaylightRecord highRecord low
January8.8°2.8°62 mm9.9 h19.1° (1969)-4.5° (1998)
February9.0°3.0°73 mm10.7 h21.3° (1962)-6.8° (1984)
March12.0°6.1°117 mm11.7 h22.7° (2024)-1.4° (1941)
April16.5°11.4°119 mm12.9 h23.7° (2024)3.1° (2010)
May20.4°15.9°135 mm13.9 h27.3° (2023)7.2° (1953)
June23.3°19.5°170 mm14.4 h31.2° (2022)13.0° (1949)
July26.8°23.1°130 mm14.2 h34.7° (2018)14.4° (1976)
August28.5°24.5°118 mm13.3 h34.4° (2025)19.0° (1953)
September25.5°21.4°176 mm12.2 h32.7° (2023)13.7° (2001)
October20.5°15.8°188 mm11.1 h28.7° (2024)8.0° (1980)
November15.9°10.6°101 mm10.1 h23.8° (2023)1.9° (1976)
December11.3°5.6°59 mm9.6 h22.5° (2004)-0.9° (1949)

How it has changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +2.0°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: +0.22°C per decade.

One point per year — 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: +0.23°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: 2.8 early in the record → 30.3 recently. Frost days: 16 → 2.

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

All-time high in 2018, all-time low in 1984: 34.7°C / -6.8°C.

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

Annual rainfall

~1447 mm/year on average. Last decade ran +4% vs that average. Long-term trend: +38 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 — ~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).

Yokohama — Frequently asked questions

Which is the warmest month in Yokohama?
On long-term average, the warmest month in Yokohama is August (mean about 26.3°C) and the coolest is January (about 5.7°C).
How does today's temperature in Yokohama compare to the historical average?
On 2026-07-19, Yokohama is forecast to reach a high of 35.2°C and a low of 25.6°C. The long-term average for this date (the full record since 1940) is a high of 27.2°C and a low of 23.3°C — today's high is 8.0°C warmer than that average.
How much has Yokohama warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Yokohama is about 2.0°C warmer.
How much does it rain in Yokohama?
Yokohama receives about 1447 mm of precipitation per year on long-term average, with October typically the wettest month.
What is the average temperature in Yokohama?
Over the full record (since 1940), the annual mean temperature in Yokohama is about 15.7°C. The warmest month is August and the coolest is January.
What are the average temperatures in Yokohama by month?
Average daily highs and lows for each month in Yokohama (°C, full record since 1940): January 9°/3°, February 9°/3°, March 12°/6°, April 17°/11°, May 20°/16°, June 23°/20°, July 27°/23°, August 28°/25°, September 26°/21°, October 20°/16°, November 16°/11°, December 11°/6°.
How many days a year does it rain in Yokohama?
On long-term average, Yokohama has about 139 days a year with measurable rain, totalling roughly 1447 mm.

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