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Nanjin weather by month: averages, rainfall & climate trends

Nanjin swings through a wide annual range, with 20.5°C between the monthly means of its warmest and coldest months. The heavier rain months run from April to September. Nanjin weather by month: average temperatures, rainfall, records and how the climate has changed since 1940.

Today vs average

+1.7°Chigh above average

25° / 20°Today
24° / 18°Average
see today in detail →

How it's changed

+1.1°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–491frost days a year now (2016–2025) · 4 in the 1940sfrost days a year · 4 in the 1940s93days above 30°C a year now (2016–2025) · 81 in the 1940sdays above 30°C · 81 in the 1940s+1.1°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 35 mmhigh 11°low 6°February, rain 37 mmhigh 13°low 7°March, rain 70 mmhigh 18°low 11°April, rain 113 mmhigh 23°low 16°May, rain 152 mmhigh 27°low 20°June, rain 165 mmhigh 29°low 23°July, rain 196 mmhigh 33°low 26°August, rain 170 mmhigh 33°low 26°September, rain 142 mmhigh 28°low 22°October, rain 105 mmhigh 22°low 17°November, rain 68 mmhigh 17°low 12°December, rain 42 mmhigh 12°low 7°wettest month July, 196 mm · 1,297 mm a yearsee month by month →

Right now

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

Right now

20.7°

24°feels like
89%humidity
19°dew point
3 km/hfrom SE
UV index0.0
sunrise06:52sunset18:31day length11h 39m
FriOvercast25°20°
SatOvercast21°20°
SunPartly cloudy26°19°
MonOvercast22°20°
TueOvercast21°19°
WedOvercast22°19°
ThuOvercast23°19°

On this date: October 8

Today (forecast)
25° / 20°
Average for October 8
24° / 18°

High above average · +1.7°C

  • Record high: 33.6° · 2025
  • Record low: 10.8° · 1981
  • One year ago: 34° / 24°

Every October 8 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 8 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 Nanjin is sampled from the ECMWF ERA5 reanalysis at 29.98°N, 106.27°E, with daily records since 1940.

Coordinates
29.98°N, 106.27°E
Time zone
Asia/Shanghai
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

16 of the last 31 days were warmer than the historical average for that date. Average difference: +0.4°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 year peaks in August, at around 33.0°C by mid-afternoon, with nights around 25.5°C. In a typical recent year, around 95 days reach 30°C or more. The coolest month is January, when afternoons reach about 11.0°C and overnight lows sit around 5.6°C.

The yearly total for Nanjin comes to about 1,297 mm; monthly amounts range from 35 mm in January up to 196 mm in July. Precipitation falls on roughly 129 days in a typical year.

The record here starts in 1940, and since then the annual mean in Nanjin has climbed 1.1°C from the first ten years to the last ten. That last decade has also been the warmest in the record.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 21°C. Wettest month: July (~196 mm). Whole year averages ~1,297 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 129 rainy days a year: most in July (~15), fewest in February (~6).

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.

Nanjin 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
January11.0°5.6°35 mm610.3 h19.8° (1969)−4.6° (1956)
February13.2°7.2°37 mm611.0 h27.2° (2021)−3.9° (1945)
March18.1°11.1°70 mm911.8 h33.9° (2025)0.7° (1986)
April23.2°15.7°113 mm1212.7 h36.1° (2019)3.0° (1969)
May26.6°19.5°152 mm1413.5 h39.8° (2011)10.7° (1991)
June29.1°22.7°165 mm1313.9 h40.3° (2025)14.9° (1940)
July32.5°25.7°196 mm1513.8 h43.1° (2017)19.3° (1973)
August33.0°25.5°170 mm1313.1 h44.6° (2011)19.1° (1950)
September28.0°21.7°142 mm1312.2 h43.7° (2024)14.1° (1949)
October22.0°16.6°105 mm1311.3 h36.2° (2021)6.8° (1972)
November17.2°11.8°68 mm910.5 h28.3° (1979)0.2° (1979)
December12.2°7.2°42 mm710.1 h21.1° (1968)−2.8° (1947)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.1°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: +0.12°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: +0.16°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: 81.4 early in the record → 93.4 recently. Frost days: 4 → 1.

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 2011, all-time low in 1956: 44.6°C / −4.6°C.

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

Annual rainfall

~1,297 mm/year on average. Last decade: −7% vs that average. Long-term trend: −21 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 Nanjin

Which is the warmest month in Nanjin?
On long-term average, the warmest month in Nanjin is August (mean daily temperature of about 29.0°C) and the coolest is January (about 8.5°C).
How does today's temperature in Nanjin compare to the historical average?
On October 8, 2026, Nanjin is forecast to reach a high of 25.2°C and a low of 20.2°C. The long-term average for this date (the full record since 1940) is a high of 23.5°C and a low of 17.8°C, so today's high is 1.7°C warmer than that average.
How much has Nanjin warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Nanjin is about 1.1°C warmer.
How much does it rain in Nanjin?
Nanjin receives about 1,297 mm of precipitation per year on long-term average, with July typically the wettest month.
What is the average temperature in Nanjin?
Over the full record (since 1940), the annual mean temperature in Nanjin is about 19.0°C. The warmest month is August and the coolest is January.
What are the average temperatures in Nanjin by month?
Average daily highs and lows for each month in Nanjin (°C, full record since 1940): January 11°/6°, February 13°/7°, March 18°/11°, April 23°/16°, May 27°/20°, June 29°/23°, July 33°/26°, August 33°/26°, September 28°/22°, October 22°/17°, November 17°/12°, December 12°/7°.
What is the weather like in Nanjin in summer?
June to August is summer in Nanjin, and it is wet and hot. June starts at 29°C by day and 23°C at night; by August it is 33°C and 26°C. Rain is steady at around 177 mm a month, spread over roughly 14 days. It is the wettest season of the year.
What is the weather like in Nanjin in winter?
December to February is winter in Nanjin, and it is cool. Daytime highs sit at 11–13°C and nights at 6–7°C; January is the coldest month. Rain falls on about 6 days a month, adding up to around 38 mm. No season is drier.
What is the weather like in Nanjin in spring?
March to May is spring in Nanjin, and it is wet and pleasantly warm. It warms from 18°C by day and 11°C at night in March to 27°C and 20°C in May. Rain picks up through the season: 9 rainy days and 70 mm in March, 14 days and 152 mm in May.
What is the weather like in Nanjin in autumn?
Autumn in Nanjin (September to November) is wet and pleasantly warm. September is still 28°C by day and 22°C at night; by November it is down to 17°C and 12°C. Rain eases through the season: 13 rainy days and 142 mm in September, 9 days and 68 mm in November.
How many days a year does it rain in Nanjin?
On long-term average, Nanjin has about 129 days a year with at least 2 mm of rain or snow. The annual total is roughly 1,297 mm.

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