Chicago Weather

September 2026

Historical data
Average Temperature
23.5 °C
High
/
18.0 °C
Low
186.4mm
Precipitation
34.2°C
Peak Temp
11.6°C
Low Temp
30
Days Count

Temperature Trends

Daily high, low, and average

Weather Extremes

Most notable conditions during this period

Period High

34.2°C
Wednesday, September 2

Coolest Day

17.1°C
Tuesday, September 22

Period Low

11.6°C
Sunday, September 27

Compare with historical weather

Load the same period from the previous 15 years.

Weather Insights

Key findings from analysis for selected period

Highly Variable Temperatures

Worth noting

Temperature swings from 11.6°C to 34.2°C (22.6°C range).

Variable Temperatures

Worth noting

Large temperature swings (22.6°C range) for a month.

High Rainfall Period

Worth noting

186mm of rain over 30 days.

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2 Exceptional Weather Events

Info

The most extreme days in this period:

Sep 2 Heat

Hottest day: 34.2°C

Sep 17 Rain

Heavy rain: 36.5mm in one day

3 Extreme Heat Index Days

Worth noting

3 days with dangerous heat index levels (45.6°C average). Temperature 32.6°C combined with 78% humidity creates hazardous conditions.

High Humidity Levels

Info

Average humidity of 80% indicates persistently moist air conditions. Heat sensation amplified during warm periods (23.5°C average temperature).

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Consistent Humidity Levels

Notable

Stable humidity conditions with only 24% variation (70%-94%). Predictable moisture levels throughout period.

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