Decatur (IL)
May
Weather in Decatur, Illinois for May 2027
Your guide to Decatur weather in May - trends and predictions
In general, the average temperature in Decatur at the beginning of May is 19.1 °C. As the month progressed, temperatures tended to significantly warm up, reaching an average of 22.9 °C by the end of May.
The climate of Decatur in May is notably wet, with an average of 13 rainy days, and a total of 199.4 mm of precipitation.
Is May a good time to visit Decatur? check out the best time to travel to Decatur page.
✨ Is May a good time to visit Decatur? – Ask the AI Weatherman
Temperatures
Rain 🌧️
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18
Dry days
13
Rainy days
0
Snow days
22°/12°
Temperatures
22 km/h
Avg max wind
73 %
Avg humidity
Decatur Weather May
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Temperatures trend during May in Decatur
See the weather trend as well as the moving average line
May weather in Decatur day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| May 1 |  Thundery outbreaks possible | 20° /12° | 46.5 mm | 7 | |
| May 2 |  Light rain | 19° /10° | 2.7 mm | 6 | |
| May 3 |  Patchy rain possible | 19° /11° | 2.3 mm | 6 | |
| May 4 |  Patchy light rain with thunder | 19° /10° | 18.2 mm | 5 | |
| May 5 | Patchy rain possible | 17° /10° | 2.3 mm | 4 | |
| May 6 |  Overcast | 18° /11° | 0.2 mm | 4 | |
| May 7 | Light rain shower | 22° /12° | 2.1 mm | 7 | |
| May 8 | Patchy light rain with thunder | 20° /11° | 9.2 mm | 5 | |
| May 9 | Patchy rain possible | 21° /9° | 0.1 mm | 6 | |
| May 10 | Patchy rain possible | 20° /9° | 1.7 mm | 7 | |
| May 11 |  Partly cloudy | 22° /10° | 0.1 mm | 7 | |
| May 12 | Patchy rain possible | 23° /12° | 1.4 mm | 7 | |
| May 13 | Light rain | 20° /13° | 3.7 mm | 6 | |
| May 14 | Light rain | 21° /11° | 3.8 mm | 7 | |
| May 15 | Patchy rain possible | 23° /15° | 1.9 mm | 6 | |
| May 16 |  Moderate rain | 24° /16° | 10.4 mm | 6 | |
| May 17 | Light rain | 23° /16° | 3.1 mm | 7 | |
| May 18 | Light rain | 24° /15° | 6.3 mm | 6 | |
| May 19 |  Heavy rain | 23° /15° | 26.7 mm | 5 | |
| May 20 | Heavy rain | 23° /13° | 30.7 mm | 6 | |
| May 21 | Thundery outbreaks possible | 23° /15° | 9.5 mm | 5 | |
| May 22 | Light rain | 20° /13° | 2.8 mm | 5 | |
| May 23 | Patchy rain possible | 22° /13° | 0.1 mm | 4 | |
| May 24 |  Moderate or heavy rain with thunder | 24° /15° | 3.4 mm | 6 | |
| May 25 |  Sunny | 21° /13° | 0 mm | 6 | |
| May 26 | Moderate or heavy rain with thunder | 23° /13° | 6.6 mm | 7 | |
| May 27 | Patchy rain possible | 22° /14° | 2.3 mm | 7 | |
| May 28 | Patchy rain possible | 22° /14° | 0.1 mm | 7 | |
| May 29 | Patchy rain possible | 21° /11° | 0 mm | 6 | |
| May 30 | Partly cloudy | 25° /12° | 0 mm | 7 | |
| May 31 | Patchy rain possible | 26° /14° | 1.3 mm | 7 | |
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Important Notice
Our weather forecast for Decatur in May is based on the analysis of historical data rather than real-time forecast models. While this provides a general overview, weather conditions can change. We recommend that you check the Decatur forecast closer to your planned date for the most up-to-date weather information.
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Decatur in May - FAQ
What are the expected maximum and minimum temperatures in Decatur during May?
Enjoy moderate daytime temperatures of up to 22° and cooler nights around 12°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Decatur during May?
Significant rainfall exceeding 199.4 mm is expected in Decatur during May, occurring over more than 13 days. Preparing for wet conditions is recommended in your planning.
What are the typical wind conditions in Decatur during May?
The average wind speed in Decatur during May is 22 km/h, suggesting breezy to windy conditions, depending on your activities.
May rainfall patterns in Decatur
Explore the daily rainfall trends and prepare for Decaturs May weather 💧
Typically, Decatur has 13 rainy days in May with a total of 199.4 mm of rainfall.
UV exposure in Decatur during May
Stay informed about UV levels for safe outdoor activities throughout the month of May ☀️
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