Decatur weather live forecast

Today's maximum temperature in Decatur is expected to be 34°C. Select a day from the live weather forecast for Decatur, Illinois, USA for more weather parameters.

5-day weather forecast updated at 04:01 on Monday 28th July 2025 GMT

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The 5-day weather forecast for Illinois (Decatur) is provided by the Swiss meteorological agency, meteoblue. Find out more about our data sources.

Decatur weather forecast by day

Below are the detailed weather forecasts for Decatur for the next 5 days.

Decatur weather for Monday 28th July 2025

Expect scattered clouds in Decatur, Illinois with a maximum temperature of 34°C, high levels of heat & humidity, maximum UV of 8 (Very High) and 8 hours of bright sunshine. There are 0 mm of rainfall expected and little or no wind of 6 kph from the west.

  • 34°C maximum temperature34
    °C maximum temperature
  • 23°C minimum temperature23
    °C minimum temperature
  • Scattered clouds
    scattered clouds
  • 8 hours of bright sunshine8
    hours of sunshine
  • UV (maximum) index 8 (Very High)8
    UV index (Very High)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • High heat & humidityH
    high heat & humidity
  • Little or no wind of 6 kph from the West6
    kph wind from W

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Decatur weather for Tuesday 29th July 2025

Expect isolated thunderstorms in Decatur, Illinois with a maximum temperature of 34°C, high levels of heat & humidity, maximum UV of 9 (Very High) and 10 hours of bright sunshine. There are 2-5 mm of rainfall expected with 6% chance of some rain and little or no wind of 4 kph from the west.

  • 34°C maximum temperature34
    °C maximum temperature
  • 25°C minimum temperature25
    °C minimum temperature
  • Isolated thunderstorms
    isolated thunderstorms
  • 10 hours of bright sunshine10
    hours of sunshine
  • UV (maximum) index 9 (Very High)9
    UV index (Very High)
  • 6% chance of some rain6
    % chance of some rain
  • 2-5 mm of rainfall expected<5
    mm of rainfall expected
  • High heat & humidityH
    high heat & humidity
  • Little or no wind of 4 kph from the West4
    kph wind from W

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Decatur weather for Wednesday 30th July 2025

Expect isolated thunderstorms in Decatur, Illinois with a maximum temperature of 31°C, moderate levels of heat & humidity, maximum UV of 6 (High) and 9 hours of bright sunshine. There are 0-2 mm of rainfall expected with 65% chance of some rain and a light breeze of 7 kph from the north-east.

  • 31°C maximum temperature31
    °C maximum temperature
  • 23°C minimum temperature23
    °C minimum temperature
  • Isolated thunderstorms
    isolated thunderstorms
  • 9 hours of bright sunshine9
    hours of sunshine
  • UV (maximum) index 6 (High)6
    UV index (High)
  • 65% chance of some rain65
    % chance of some rain
  • 0-2 mm of rainfall expected<2
    mm of rainfall expected
  • Moderate heat & humidityM
    moderate heat & humidity
  • Light breeze of 7 kph from the North-East7
    kph wind from NE

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Decatur weather for Thursday 31st July 2025

Expect isolated thunderstorms in Decatur, Illinois with a maximum temperature of 25°C, maximum UV of 1 (Low) and 2 hours of bright sunshine. There are 2-5 mm of rainfall expected with 55% chance of some rain and a gentle breeze of 13 kph from the north-east.

  • 25°C maximum temperature25
    °C maximum temperature
  • 19°C minimum temperature19
    °C minimum temperature
  • Isolated thunderstorms
    isolated thunderstorms
  • 2 hours of bright sunshine2
    hours of sunshine
  • UV (maximum) index 1 (Low)1
    UV index (Low)
  • 55% chance of some rain55
    % chance of some rain
  • 2-5 mm of rainfall expected<5
    mm of rainfall expected
  • No heat & humidity0
    no heat & humidity
  • Gentle breeze of 13 kph from the North-East13
    kph wind from NE

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Decatur weather for Friday 1st August 2025

Expect scattered clouds in Decatur, Illinois with a maximum temperature of 25°C, maximum UV of 9 (Very High) and 10 hours of bright sunshine. There are 0 mm of rainfall expected and a gentle breeze of 13 kph from the north-east.

  • 25°C maximum temperature25
    °C maximum temperature
  • 17°C minimum temperature17
    °C minimum temperature
  • Scattered clouds
    scattered clouds
  • 10 hours of bright sunshine10
    hours of sunshine
  • UV (maximum) index 9 (Very High)9
    UV index (Very High)
  • 0 mm of rainfall expected0
    mm of rainfall expected
  • No heat & humidity0
    no heat & humidity
  • Gentle breeze of 13 kph from the North-East13
    kph wind from NE

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Metric (°C / mm)  |  Imperial (°F / inches)

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