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Shanghai weather by month: averages, rainfall & climate trends

The Yangtze delta's global metropolis wears its humid subtropical climate openly: steamy summers, typhoon-season drama, and cool, surprisingly brisk winters when Siberian air can reach straight through the city's towers. Shanghai weather by month: average temperatures, rainfall, records and how the climate has changed since 1940.

Today vs average

+9.6°Chigh well above average

31° / 22°Today
22° / 16°Average
see today in detail →

How it's changed

+1.7°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4913frost days a year now (2016–2025) · 25 in the 1940sfrost days a year · 25 in the 1940s73days above 30°C a year now (2016–2025) · 47 in the 1940sdays above 30°C · 47 in the 1940s+1.7°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 51 mmhigh 8°low 2°February, rain 64 mmhigh 9°low 3°March, rain 94 mmhigh 13°low 7°April, rain 118 mmhigh 19°low 12°May, rain 146 mmhigh 23°low 17°June, rain 266 mmhigh 27°low 22°July, rain 173 mmhigh 31°low 26°August, rain 138 mmhigh 31°low 26°September, rain 137 mmhigh 27°low 22°October, rain 65 mmhigh 22°low 16°November, rain 52 mmhigh 17°low 11°December, rain 39 mmhigh 11°low 4°wettest month June, 266 mm · 1,343 mm a yearsee month by month →

Right now

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

Right now

21.4°

24°feels like
84%humidity
19°dew point
6 km/hfrom N
UV index0.0
sunrise05:58sunset17:19day length11h 21m
TodayOvercast31°22°
MonOvercast24°21°
TuePartly cloudy31°22°
WedOvercast21°17°
ThuOvercast20°15°
FriPartly cloudy22°17°
SatLight rain23°20°

On this date: October 18

Today (forecast)
31° / 22°
Average for October 18
22° / 16°

High well above average · +9.6°C

  • Record high: 29.9° · 2024
  • Record low: 11.1° · 1963
  • One year ago: 23° / 20°

Every October 18 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 18 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 Shanghai is sampled from the ECMWF ERA5 reanalysis at 31.22°N, 121.46°E, with daily records since 1940.

Coordinates
31.22°N, 121.46°E
Time zone
Asia/Shanghai
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

25 of the last 31 days were warmer than the historical average 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 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

Shanghai spreads along the Yangtze Estuary on China's central coast, with a humid subtropical climate (Köppen Cfa) of four distinct seasons. Summers are hot and humid; winters are cool and damp, often cold, with northwesterly winds arriving from Siberia capable of dropping temperatures sharply. Autumn tends to be the clearest and most settled season. The coastal position exposes the city to typhoons in summer and early autumn, which can deliver intense rainfall and storm surges.

Shanghai sits at the confluence of two great climatic systems (the cold continental interior to the north and the humid subtropical coastline), making for variable and sometimes extreme weather. On 21 July 2017 the city set a new all-time temperature record, equalled on 13 July 2022, during heat events that highlighted a warming trend across recent decades.

The warmest month is July, with typical afternoon highs of 31.2°C and nights around 25.9°C. On about 135 nights a year, the temperature never drops below 20°C. The coolest month is January, when afternoons reach about 7.7°C and overnight lows sit around 1.7°C. Around 13 days a year dip below freezing.

In total, Shanghai averages about 1,343 mm of precipitation a year; June is usually the wettest month (266 mm) and December the driest (39 mm).

The record here starts in 1940, and since then the annual mean in Shanghai has climbed 1.7°C from the first ten years to the last ten. Days above 30°C have grown noticeably more frequent, from around 45 a year in the first decade to about 75 in the last.

Sources:en.wikipedia.orgbritannica.comcma.gov.cn

Climate graph (climograph)

July is the warmest month, January the coolest: a yearly swing of 24°C. Wettest month: June (~266 mm). Whole year averages ~1,343 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 104 rainy days a year: most in June (~13), fewest in December (~5).

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.

Shanghai 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 lowRainRainy daysDaylightRecord highRecord low
January7.7°1.7°51 mm610.2 h23.2° (1950)−9.4° (1958)
February8.9°3.0°64 mm710.9 h24.4° (2014)−8.5° (1980)
March12.9°6.8°94 mm1011.8 h29.3° (2025)−3.6° (1958)
April18.5°12.0°118 mm1012.8 h32.0° (1967)2.0° (1962)
May23.3°17.1°146 mm1013.6 h34.6° (1991)9.0° (1965)
June26.8°21.6°266 mm1314.0 h37.7° (1946)13.5° (1954)
July31.2°25.9°173 mm1213.8 h38.8° (2013)18.0° (1976)
August30.9°25.8°138 mm1113.1 h39.5° (2013)19.7° (1974)
September27.0°22.0°137 mm1012.2 h40.1° (1946)13.2° (1957)
October22.0°16.4°65 mm511.2 h35.3° (2025)4.7° (1978)
November16.6°10.6°52 mm510.4 h28.4° (2023)−5.0° (1979)
December10.5°4.1°39 mm510.0 h22.8° (2023)−7.0° (1967)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.7°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: +0.21°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

Mar–May is warming fastest: +0.29°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: 46.6 early in the record → 73.2 recently. Frost days: 25 → 13.

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 1946, all-time low in 1958: 40.1°C / −9.4°C.

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

Annual rainfall

~1,343 mm/year on average. Last decade: +2% vs that average. Long-term trend: +7 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 Shanghai

Which is the warmest month in Shanghai?
On long-term average, the warmest month in Shanghai is July (mean daily temperature of about 28.1°C) and the coolest is January (about 4.6°C).
How does today's temperature in Shanghai compare to the historical average?
On October 18, 2026, Shanghai is forecast to reach a high of 31.3°C and a low of 21.5°C. The long-term average for this date (the full record since 1940) is a high of 21.7°C and a low of 16.0°C, so today's high is 9.6°C warmer than that average.
How much has Shanghai warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Shanghai is about 1.7°C warmer.
How much does it rain in Shanghai?
Shanghai receives about 1,343 mm of precipitation per year on long-term average, with June typically the wettest month.
What is the average temperature in Shanghai?
Over the full record (since 1940), the annual mean temperature in Shanghai is about 16.6°C. The warmest month is July and the coolest is January.
What are the average temperatures in Shanghai by month?
Average daily highs and lows for each month in Shanghai (°C, full record since 1940): January 8°/2°, February 9°/3°, March 13°/7°, April 19°/12°, May 23°/17°, June 27°/22°, July 31°/26°, August 31°/26°, September 27°/22°, October 22°/16°, November 17°/11°, December 11°/4°.
What is the weather like in Shanghai in summer?
In summer, June through August, Shanghai is wet and warm. It warms from 27°C by day and 22°C at night in June to 31°C and 26°C in August. Rain eases through the season: 13 rainy days and 266 mm in June, 11 days and 138 mm in August. It is the wettest season of the year.
What is the weather like in Shanghai in winter?
In winter, December through February, Shanghai is on the cool side. Afternoons run 8–11°C and nights 2–4°C; January is the coldest month. Rain rises from 39 mm on 5 days in December to 64 mm on 7 days in February. No season is drier.
What is the weather like in Shanghai in spring?
Spring in Shanghai (March to May) is wet and mild. It warms from 13°C by day and 7°C at night in March to 23°C and 17°C in May. Rain rises from 94 mm in March to 146 mm in May.
What is the weather like in Shanghai in autumn?
In autumn, September through November, Shanghai is mild. September still brings 27°C afternoons and 22°C nights, November only 17°C and 11°C. Rain falls off from 137 mm on 10 days in September to 52 mm on 5 days in November.
How many days a year does it rain in Shanghai?
On long-term average, Shanghai has about 104 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,343 mm.

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