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Jundiaí weather by month: averages, rainfall & climate trends

Temperature-wise, the seasons in Jundiaí are gentle: monthly means drift only 6.2°C over the whole year. The heavier rain months run from October to March. Jundiaí weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+0.2°Chigh near average

25° / 14°Today
25° / 16°Average
see today in detail →

How it's changed

+1.7°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4974days above 30°C a year now (2016–2025) · 6 in the 1940sdays above 30°C · 6 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 228 mmhigh 27°low 19°February, rain 184 mmhigh 27°low 19°March, rain 150 mmhigh 27°low 18°April, rain 75 mmhigh 25°low 16°May, rain 73 mmhigh 23°low 14°June, rain 53 mmhigh 22°low 12°July, rain 48 mmhigh 22°low 12°August, rain 42 mmhigh 24°low 13°September, rain 86 mmhigh 25°low 15°October, rain 142 mmhigh 26°low 16°November, rain 152 mmhigh 26°low 17°December, rain 220 mmhigh 26°low 18°wettest month January, 228 mm · 1,454 mm a yearsee month by month →

Right now

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

Right now

23.8°

23°feels like
48%humidity
12°dew point
7 km/hfrom W
UV index9.5
sunrise05:31sunset18:13day length12h 43m
TodayMostly clear25°14°
TueMostly clear26°14°
WedPartly cloudy28°15°
ThuOvercast26°18°
FriLight rain22°19°
SatOvercast22°20°
SunShowers20°17°

On this date: October 19

Today (forecast)
25° / 14°
Average for October 19
25° / 16°

High near average · +0.2°C

  • Highest since 1940: 36.8° · 2014
  • Lowest since 1940: 11.2° · 1989
  • One year ago: 19° / 13°

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 Jundiaí is sampled from the ECMWF ERA5 reanalysis at 23.19°S, 46.88°W, with daily records since 1940.

Coordinates
23.19°S, 46.88°W
Time zone
America/Sao Paulo
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

21 of the last 31 days were warmer than the historical average for that date. Average difference: +1.1°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 February, with typical afternoon highs of 27.3°C and nights around 18.9°C. Around 55 nights a year stay above 20°C. The coolest month is July, when afternoons reach about 22.2°C and overnight lows sit around 11.8°C. Freezing temperatures almost never occur.

Jundiaí picks up roughly 1,454 mm a year, with a peak of 228 mm in January and as little as 42 mm in August.

The record here starts in 1940, and since then the annual mean in Jundiaí has climbed 1.7°C from the first ten years to the last ten. The count of days past 30°C has risen from roughly 6 a year to 75 between the record's first and last decades.

Climate graph (climograph)

February is the warmest month, July the coolest: a yearly swing of 6°C. Wettest month: January (~228 mm). Whole year averages ~1,454 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.

Jundiaí 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
January27.1°18.9°228 mm13.3 h37.4° (2015)12.0° (1943)
February27.3°18.9°184 mm12.8 h37.0° (2014)13.4° (1991)
March26.8°18.3°150 mm12.2 h33.3° (2018)11.4° (1987)
April25.2°16.5°75 mm11.5 h32.3° (2016)6.0° (1971)
May23.0°14.0°73 mm10.9 h31.7° (2024)3.1° (1968)
June22.1°12.4°53 mm10.6 h29.4° (2010)0.0° (1979)
July22.2°11.8°48 mm10.7 h29.9° (2014)1.6° (2000)
August24.0°12.9°42 mm11.2 h33.0° (2005)2.7° (1987)
September25.3°14.6°86 mm11.9 h36.9° (1961)4.2° (2002)
October25.6°16.2°142 mm12.6 h37.6° (2020)7.9° (1974)
November25.9°16.9°152 mm13.1 h36.5° (2023)9.3° (1956)
December26.5°18.2°220 mm13.4 h36.8° (2013)11.5° (1964)

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: +0.24°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: +0.29°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: 6.4 early in the record → 73.6 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 2020, coldest in 1979: 37.6°C / 0.0°C.

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

Annual rainfall

~1,454 mm/year on average. Last decade: −18% vs that average. Long-term trend: −40 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 Jundiaí

Which is the warmest month in Jundiaí?
On long-term average, the warmest month in Jundiaí is February (mean daily temperature of about 22.6°C) and the coolest is July (about 16.4°C).
How does today's temperature in Jundiaí compare to the historical average?
On October 19, 2026, Jundiaí is forecast to reach a high of 24.8°C and a low of 14.1°C. The long-term average for this date (the full record since 1940) is a high of 24.6°C and a low of 16.2°C, so today's high is about equal to that average.
How much has Jundiaí warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Jundiaí is about 1.7°C warmer.
How much does it rain in Jundiaí?
Jundiaí receives about 1,454 mm of precipitation per year on long-term average, with January typically the wettest month.
What is the average temperature in Jundiaí?
Over the full record (since 1940), the annual mean temperature in Jundiaí is about 19.9°C. The warmest month is February and the coolest is July.
What are the average temperatures in Jundiaí by month?
Average daily highs and lows for each month in Jundiaí (°C, full record since 1940): January 27°/19°, February 27°/19°, March 27°/18°, April 25°/16°, May 23°/14°, June 22°/12°, July 22°/12°, August 24°/13°, September 25°/15°, October 26°/16°, November 26°/17°, December 26°/18°.
What is the weather like in Jundiaí in summer?
December to February is summer in Jundiaí, and it is wet and warm. Expect 26–27°C by day and 18–19°C at night, with February the warmest month. About 211 mm of rain a month. No season is wetter.
What is the weather like in Jundiaí in winter?
June to August is winter in Jundiaí, and it is pleasantly warm. Daytime highs sit at 22–24°C and nights at 12–13°C; July is the coldest month. Rain is steady at around 48 mm a month. It is the driest season of the year.
What is the weather like in Jundiaí in spring?
Spring in Jundiaí (September to November) is wet and pleasantly warm. Afternoons run 25–26°C and nights 15–17°C; November is the warmest month. Rain picks up through the season, 86 mm in September to 152 mm in November.
What is the weather like in Jundiaí in autumn?
March to May is autumn in Jundiaí, and it is pleasantly warm. It cools from 27°C by day and 18°C at night in March to 23°C and 14°C in May. Rain eases through the season, 150 mm in March to 73 mm in May.

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