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Chengdu weather by month: averages, rainfall & climate trends

Sheltered deep in the Sichuan Basin, Chengdu lives under famously grey skies, a mild, humid, cloud-wrapped climate that colours everything about life on the plain. Chengdu weather by month: average temperatures, rainfall, records and how the climate has changed since 1940.

Today vs average

−1.2°Chigh near average

19° / 17°Today
21° / 15°Average
see today in detail →

How it's changed

+1.4°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–494frost days a year now (2016–2025) · 17 in the 1940sfrost days a year · 17 in the 1940s83days above 30°C a year now (2016–2025) · 37 in the 1940sdays above 30°C · 37 in the 1940s+1.4°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 8 mmhigh 10°low 3°February, rain 11 mmhigh 12°low 5°March, rain 24 mmhigh 17°low 9°April, rain 50 mmhigh 23°low 14°May, rain 73 mmhigh 27°low 19°June, rain 149 mmhigh 29°low 21°July, rain 320 mmhigh 30°low 23°August, rain 318 mmhigh 30°low 23°September, rain 164 mmhigh 26°low 19°October, rain 46 mmhigh 21°low 15°November, rain 22 mmhigh 16°low 10°December, rain 8 mmhigh 11°low 5°wettest month July, 320 mm · 1,194 mm a yearsee month by month →

Right now

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

Right now

17.9°

19°feels like
82%humidity
15°dew point
3 km/hfrom N
UV index0.8
sunrise07:07sunset18:29day length11h 22m
TodayOvercast19°17°
MonPartly cloudy23°17°
TueMostly clear26°17°
WedOvercast19°17°
ThuOvercast18°15°
FriOvercast22°15°
SatOvercast20°16°

On this date: October 18

Today (forecast)
19° / 17°
Average for October 18
21° / 15°

High near average · −1.2°C

  • Record high: 26.8° · 2015
  • Record low: 10.3° · 1987
  • One year ago: 24° / 17°

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 Chengdu is sampled from the ECMWF ERA5 reanalysis at 30.67°N, 104.07°E, with daily records since 1940.

Coordinates
30.67°N, 104.07°E
Time zone
Asia/Shanghai
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

29 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

Chengdu occupies the Chengdu Plain in the western Sichuan Basin, with the steep wall of the Longmen Mountains rising to its northwest and the Qionglai range to its west. Its climate is monsoon-influenced humid subtropical (Köppen Cwa): humid the year round, with rainfall concentrated in the warmer months and falling most frequently in July and August. Far to the north, the Qin Mountains block the worst of the cold Siberian air, keeping winters mild, while persistent cloud cover means the city sees fewer hours of sun in a year than large parts of Northern Europe.

Snow is rare, though frost visits periodically in winter. The sharpest recent test came in the summer of 2022, when a heat wave of exceptional severity and persistence settled over the region: drought spread across Sichuan, water supplies to farms, businesses and industry were curtailed, electricity ran short, and artificial rainfall was induced in parts of the province before the strain finally eased in late August.

July brings the year's peak warmth, with afternoons typically reaching 30.1°C and nights around 23.1°C. Around 115 nights a year stay above 20°C. At the other extreme, January brings afternoon highs of about 9.8°C and typical overnight lows of 3.0°C.

Chengdu picks up roughly 1,194 mm a year, with a peak of 320 mm in July and as little as 8 mm in January.

The record here starts in 1940, and since then the annual mean in Chengdu has climbed 1.4°C from the first ten years to the last ten. Days above 30°C have grown noticeably more frequent, from around 35 a year in the first decade to about 85 in the last.

Sources:en.wikipedia.orgen.wikipedia.orgcma.gov.cn

Climate graph (climograph)

July is the warmest month, January the coolest: a yearly swing of 20°C. Wettest month: July (~320 mm). Whole year averages ~1,194 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 89 rainy days a year: most in July (~19), fewest in January (~1).

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.

Chengdu 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
January9.8°3.0°8 mm110.2 h18.7° (2013)−5.5° (1955)
February12.0°4.9°11 mm110.9 h24.4° (2021)−4.7° (1945)
March17.3°9.3°24 mm411.8 h32.7° (2007)−0.9° (1951)
April22.9°14.3°50 mm612.8 h36.7° (2019)3.1° (1969)
May26.9°18.6°73 mm813.6 h38.4° (2006)9.4° (1965)
June28.9°21.4°149 mm1014.0 h39.5° (1960)14.7° (1966)
July30.1°23.1°320 mm1913.8 h40.1° (2002)17.6° (1989)
August29.8°22.6°318 mm1913.1 h41.6° (2022)15.8° (1999)
September25.6°19.4°164 mm1212.2 h37.9° (2002)12.0° (1970)
October20.9°15.0°46 mm611.2 h31.8° (2016)2.5° (1986)
November16.0°9.7°22 mm310.4 h25.1° (2006)−5.5° (1979)
December11.0°4.5°8 mm110.0 h20.1° (1968)−5.7° (1944)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.4°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: +0.17°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

Jun–Aug is warming fastest: +0.22°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: 37.3 early in the record → 82.7 recently. Frost days: 17 → 4.

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 2022, all-time low in 1944: 41.6°C / −5.7°C.

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

Annual rainfall

~1,194 mm/year on average. Last decade: −6% vs that average. Long-term trend: −45 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 Chengdu

Which is the warmest month in Chengdu?
On long-term average, the warmest month in Chengdu is July (mean daily temperature of about 26.3°C) and the coolest is January (about 6.3°C).
How does today's temperature in Chengdu compare to the historical average?
On October 18, 2026, Chengdu is forecast to reach a high of 19.3°C and a low of 17.3°C. The long-term average for this date (the full record since 1940) is a high of 20.5°C and a low of 14.8°C, so today's high is 1.2°C cooler than that average.
How much has Chengdu warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Chengdu is about 1.4°C warmer.
How much does it rain in Chengdu?
Chengdu receives about 1,194 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Chengdu?
Over the full record (since 1940), the annual mean temperature in Chengdu is about 17.3°C. The warmest month is July and the coolest is January.
What are the average temperatures in Chengdu by month?
Average daily highs and lows for each month in Chengdu (°C, full record since 1940): January 10°/3°, February 12°/5°, March 17°/9°, April 23°/14°, May 27°/19°, June 29°/21°, July 30°/23°, August 30°/23°, September 26°/19°, October 21°/15°, November 16°/10°, December 11°/5°.
What is the weather like in Chengdu in summer?
Summer in Chengdu (June to August) is wet and warm. Afternoons run 29–30°C and nights 21–23°C; July is the warmest month. Rain picks up through the season: 10 rainy days and 149 mm in June, 19 days and 318 mm in August. No season is wetter.
What is the weather like in Chengdu in winter?
In winter, December through February, Chengdu is dry and on the cool side. Expect 10–12°C by day and 3–5°C at night, with January the coldest month. Hardly any rain falls.
What is the weather like in Chengdu in spring?
Spring in Chengdu (March to May) is pleasantly warm. March starts at 17°C by day and 9°C at night; by May it is 27°C and 19°C. Rain picks up through the season: 4 rainy days and 24 mm in March, 8 days and 73 mm in May.
What is the weather like in Chengdu in autumn?
In autumn, September through November, Chengdu is mild. It cools from 26°C by day and 19°C at night in September to 16°C and 10°C in November. Rain falls off from 164 mm on 12 days in September to 22 mm on 3 days in November.
How many days a year does it rain in Chengdu?
On long-term average, Chengdu has about 89 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,194 mm.

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