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Mengzi weather by month: averages, rainfall & climate trends

Mengzi has well-marked seasons, with 11.0°C between its warmest and coolest monthly means. Most of the year's rain is packed into the months from May to September. Mengzi weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+4.3°Chigh well above average

27° / 19°Today
23° / 16°Average
see today in detail →

How it's changed

+1.9°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4916days above 30°C a year now (2016–2025) · 0 in the 1940sdays above 30°C · 0 in the 1940s+1.9°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 41 mmhigh 16°low 8°February, rain 43 mmhigh 18°low 9°March, rain 73 mmhigh 22°low 12°April, rain 108 mmhigh 25°low 16°May, rain 181 mmhigh 26°low 19°June, rain 266 mmhigh 26°low 20°July, rain 288 mmhigh 26°low 20°August, rain 302 mmhigh 26°low 20°September, rain 162 mmhigh 26°low 19°October, rain 97 mmhigh 23°low 16°November, rain 52 mmhigh 20°low 12°December, rain 34 mmhigh 17°low 9°wettest month August, 302 mm · 1,649 mm a yearsee month by month →

Right now

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

Right now

21.7°

24°feels like
80%humidity
18°dew point
8 km/hfrom SE
UV index0.0
sunrise07:05sunset18:37day length11h 33m
TodayOvercast27°19°
TuePartly cloudy29°20°
WedOvercast27°20°
ThuPartly cloudy27°19°
FriPartly cloudy29°19°
SatClear30°19°
SunPartly cloudy30°18°

On this date: October 19

Today (forecast)
27° / 19°
Average for October 19
23° / 16°

High well above average · +4.3°C

  • Highest since 1940: 27.7° · 1969
  • Lowest since 1940: 9.1° · 1945
  • One year ago: 26° / 18°

Every October 19 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 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 Mengzi is sampled from the ECMWF ERA5 reanalysis at 23.37°N, 103.38°E, with daily records since 1940.

Coordinates
23.37°N, 103.38°E
Time zone
Asia/Shanghai
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

28 of the last 31 days were warmer than the historical average for that date. Average difference: +2.0°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

June brings the year's peak warmth, with afternoons typically reaching 26.5°C and nights around 20.4°C. On about 110 nights a year, the temperature never drops below 20°C. At the other extreme, January brings afternoon highs of about 16.4°C and typical overnight lows of 8.2°C. Freezing temperatures almost never occur.

The yearly total for Mengzi comes to about 1,649 mm; monthly amounts range from 34 mm in December up to 302 mm in August.

Over the full record (since 1940), the annual mean temperature in Mengzi has risen by 1.9°C between its first decade and its last. The count of days past 30°C has risen from roughly 0 a year to 15 between the record's first and last decades.

Climate graph (climograph)

June is the warmest month, January the coolest: a yearly swing of 11°C. Wettest month: August (~302 mm). Whole year averages ~1,649 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: the record's own proxy for how sunny the month is.

Mengzi 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 lowRainDaylightHighestLowest
January16.4°8.2°41 mm10.7 h25.7° (2005)−1.6° (1974)
February18.4°9.3°43 mm11.2 h28.8° (1999)0.1° (1968)
March22.0°12.3°73 mm11.8 h30.6° (2014)1.2° (1986)
April24.8°15.7°108 mm12.5 h32.8° (2010)6.2° (1970)
May26.3°18.7°181 mm13.1 h34.1° (1963)10.3° (1990)
June26.5°20.4°266 mm13.4 h33.0° (2023)13.0° (2013)
July26.4°20.4°288 mm13.3 h32.1° (2015)16.2° (1965)
August26.5°20.0°302 mm12.8 h32.4° (2020)14.4° (1944)
September25.6°18.6°162 mm12.1 h31.9° (2008)10.6° (2013)
October23.0°16.0°97 mm11.4 h29.7° (2016)4.4° (1978)
November20.1°12.2°52 mm10.9 h28.6° (2009)1.8° (1983)
December17.0°8.8°34 mm10.6 h26.0° (1998)−7.9° (2013)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.9°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: +0.22°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: +0.30°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: 0.0 early in the record → 15.8 recently. Frost days: 0 → 0.

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 1963, coldest in 2013: 34.1°C / −7.9°C.

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

Annual rainfall

~1,649 mm/year on average. Last decade: −2% vs that average. Long-term trend: −18 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 Mengzi

Which is the warmest month in Mengzi?
On long-term average, the warmest month in Mengzi is June (mean daily temperature of about 22.9°C) and the coolest is January (about 11.9°C).
How does today's temperature in Mengzi compare to the historical average?
On October 19, 2026, Mengzi is forecast to reach a high of 27.2°C and a low of 19.3°C. The long-term average for this date (the full record since 1940) is a high of 22.9°C and a low of 15.6°C, so today's high is 4.3°C warmer than that average.
How much has Mengzi warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Mengzi is about 1.9°C warmer.
How much does it rain in Mengzi?
Mengzi receives about 1,649 mm of precipitation per year on long-term average, with August typically the wettest month.
What is the average temperature in Mengzi?
Over the full record (since 1940), the annual mean temperature in Mengzi is about 18.4°C. The warmest month is June and the coolest is January.
What are the average temperatures in Mengzi by month?
Average daily highs and lows for each month in Mengzi (°C, full record since 1940): January 16°/8°, February 18°/9°, March 22°/12°, April 25°/16°, May 26°/19°, June 26°/20°, July 26°/20°, August 26°/20°, September 26°/19°, October 23°/16°, November 20°/12°, December 17°/9°.
What is the weather like in Mengzi in summer?
In summer, June through August, Mengzi is wet and warm. Afternoons run 26°C and nights 20°C; August is the warmest month. About 285 mm of rain a month. It is the wettest season of the year.
What is the weather like in Mengzi in winter?
In winter, December through February, Mengzi is fairly mild. Expect 16–18°C by day and 8–9°C at night, with January the coldest month. Rain is steady at around 39 mm a month. It is the driest season of the year.
What is the weather like in Mengzi in spring?
March to May is spring in Mengzi, and it is wet and pleasantly warm. March starts at 22°C by day and 12°C at night; by May it is 26°C and 19°C. Rain rises from 73 mm in March to 181 mm in May.
What is the weather like in Mengzi in autumn?
September to November is autumn in Mengzi, and it is wet and pleasantly warm. It cools from 26°C by day and 19°C at night in September to 20°C and 12°C in November. Rain eases through the season, 162 mm in September to 52 mm in November.

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