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Shinagawa weather by month: averages, rainfall & climate trends

Seasons run to extremes in Shinagawa: monthly means span 23.4°C between the coldest month and the warmest. The heavier rain months run from May to September. Shinagawa weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+6.7°Chigh well above average

27° / 17°Today
20° / 12°Average
see today in detail →

How it's changed

+2.9°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4927frost days a year now (2016–2025) · 67 in the 1940sfrost days a year · 67 in the 1940s54days above 30°C a year now (2016–2025) · 12 in the 1940sdays above 30°C · 12 in the 1940s+2.9°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 77 mmhigh 7°low 0°February, rain 90 mmhigh 8°low 0°March, rain 122 mmhigh 12°low 4°April, rain 153 mmhigh 18°low 9°May, rain 178 mmhigh 22°low 14°June, rain 295 mmhigh 25°low 18°July, rain 273 mmhigh 29°low 23°August, rain 210 mmhigh 30°low 23°September, rain 242 mmhigh 27°low 19°October, rain 146 mmhigh 21°low 13°November, rain 95 mmhigh 15°low 7°December, rain 74 mmhigh 10°low 2°wettest month June, 295 mm · 1,955 mm a yearsee month by month →

Right now

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

Right now

20.3°

22°feels like
82%humidity
17°dew point
7 km/hfrom S
UV index0.1
sunrise06:17sunset17:27day length11h 11m
WedOvercast27°17°
ThuPartly cloudy18°11°
FriLight rain20°9°
SatOvercast24°19°
SunLight rain23°20°
MonOvercast25°20°
TueOvercast23°18°

On this date: October 20

Today (forecast)
27° / 17°
Average for October 20
20° / 12°

High well above average · +6.7°C

  • Highest since 1940: 25.1° · 1997
  • Lowest since 1940: 5.3° · 1956
  • One year ago: 22° / 15°

Every October 20 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 20 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 Shinagawa is sampled from the ECMWF ERA5 reanalysis at 33.64°N, 133.01°E, with daily records since 1940.

Coordinates
33.64°N, 133.01°E
Time zone
Asia/Tokyo
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

19 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, 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

The warmest month is August, with typical afternoon highs of 30.2°C and nights around 22.9°C. On about 100 nights a year, the temperature never drops below 20°C. At the other extreme, January brings afternoon highs of about 6.7°C and typical overnight lows of −0.4°C.

In total, Shinagawa averages about 1,955 mm of precipitation a year; June is usually the wettest month (295 mm) and December the driest (74 mm). Precipitation falls on roughly 138 days in a typical year.

Over the full record (since 1940), the annual mean temperature in Shinagawa has risen by 2.9°C between its first decade and its last. Days above 30°C have grown noticeably more frequent, from around 12 a year in the first decade to about 55 in the last.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 23°C. Wettest month: June (~295 mm). Whole year averages ~1,955 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 138 rainy days a year: most in July (~17), fewest in November (~8).

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.

Shinagawa 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
January6.7°−0.4°77 mm1010.0 h19.6° (1969)−11.6° (1940)
February7.8°0.1°90 mm910.8 h21.0° (2024)−13.7° (1977)
March12.1°3.6°122 mm1111.7 h25.0° (2025)−8.7° (1968)
April18.1°9.0°153 mm1112.8 h29.3° (1973)−2.0° (1962)
May22.4°13.7°178 mm1113.7 h30.8° (2025)3.1° (1980)
June25.5°18.4°295 mm1514.2 h33.4° (2025)9.1° (1957)
July29.3°22.6°273 mm1714.0 h35.8° (1958)14.6° (1966)
August30.2°22.9°210 mm1513.3 h35.4° (2024)14.5° (1956)
September26.6°19.3°242 mm1412.2 h34.4° (2024)8.2° (1987)
October21.1°12.7°146 mm911.1 h29.8° (2022)1.6° (1986)
November15.4°7.1°95 mm810.2 h25.4° (2023)−5.0° (1976)
December9.5°2.1°74 mm89.8 h21.5° (2018)−10.6° (1980)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +2.9°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: +0.33°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: +0.37°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: 12.2 early in the record → 54.2 recently. Frost days: 67 → 27.

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 1958, coldest in 1977: 35.8°C / −13.7°C.

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

Annual rainfall

~1,955 mm/year on average. Last decade: +4% vs that average. Long-term trend: +39 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 Shinagawa

Which is the warmest month in Shinagawa?
On long-term average, the warmest month in Shinagawa is August (mean daily temperature of about 26.2°C) and the coolest is January (about 2.8°C).
How does today's temperature in Shinagawa compare to the historical average?
On October 20, 2026, Shinagawa is forecast to reach a high of 27.0°C and a low of 16.7°C. The long-term average for this date (the full record since 1940) is a high of 20.3°C and a low of 11.6°C, so today's high is 6.7°C warmer than that average.
How much has Shinagawa warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Shinagawa is about 2.9°C warmer.
How much does it rain in Shinagawa?
Shinagawa receives about 1,955 mm of precipitation per year on long-term average, with June typically the wettest month.
What is the average temperature in Shinagawa?
Over the full record (since 1940), the annual mean temperature in Shinagawa is about 14.6°C. The warmest month is August and the coolest is January.
What are the average temperatures in Shinagawa by month?
Average daily highs and lows for each month in Shinagawa (°C, full record since 1940): January 7°/0°, February 8°/0°, March 12°/4°, April 18°/9°, May 22°/14°, June 25°/18°, July 29°/23°, August 30°/23°, September 27°/19°, October 21°/13°, November 15°/7°, December 10°/2°.
What is the weather like in Shinagawa in summer?
June to August is summer in Shinagawa, and it is wet and warm. It warms from 25°C by day and 18°C at night in June to 30°C and 23°C in August. Rain is steady at around 259 mm a month, spread over roughly 16 days. It is the wettest season of the year.
What is the weather like in Shinagawa in winter?
In winter, December through February, Shinagawa is cold. Afternoons run 7–10°C and nights 0–2°C; January is the coldest month. Rain falls on about 9 days a month, adding up to around 81 mm. No season is drier.
What is the weather like in Shinagawa in spring?
March to May is spring in Shinagawa, and it is wet and fairly mild. It warms from 12°C by day and 4°C at night in March to 22°C and 14°C in May. Rain is steady at around 151 mm a month, spread over roughly 11 days.
What is the weather like in Shinagawa in autumn?
September to November is autumn in Shinagawa, and it is wet and mild. September still brings 27°C afternoons and 19°C nights, November only 15°C and 7°C. Rain eases through the season: 14 rainy days and 242 mm in September, 8 days and 95 mm in November.
How many days a year does it rain in Shinagawa?
On long-term average, Shinagawa has about 138 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,955 mm.

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