Johnson County (Iowa City)
May
Weather in Johnson County, Iowa for May 2026
Your guide to Johnson County weather in May - trends and predictions
In general, the average temperature in Johnson County at the beginning of May is 18.3 °F. As the month progressed, temperatures tended to noticeably warm up, reaching an average of 20.9 °F by the end of May.
Johnson County experiences moderate rainfall in May, with an average of 10 rainy days and a total precipitation of 79.9 mm.
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Temperatures
Rain 🌧️
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21
Dry days
10
Rainy days
0
Snow days
21°/10°
Temperatures
20 km/h
Avg max wind
72 %
Avg humidity
Johnson County Weather May
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Temperatures trend during May in Johnson County
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May weather in Johnson County day by day
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| Date | Weather | Temperatures | Rain | UV | More |
|---|---|---|---|---|---|
| May 1 |  Moderate or heavy rain shower | 18° /10° | 9 mm | 4 | |
| May 2 |  Patchy rain possible | 15° /9° | 0.4 mm | 4 | |
| May 3 | Patchy rain possible | 16° /7° | 0.8 mm | 4 | |
| May 4 |  Overcast | 18° /5° | 0 mm | 4 | |
| May 5 | Overcast | 17° /6° | 0 mm | 4 | |
| May 6 | Overcast | 21° /6° | 0 mm | 5 | |
| May 7 | Patchy rain possible | 23° /11° | 0.1 mm | 5 | |
| May 8 | Overcast | 18° /7° | 0 mm | 4 | |
| May 9 |  Sunny | 20° /3° | 0 mm | 6 | |
| May 10 | Sunny | 27° /9° | 0 mm | 7 | |
| May 11 | Sunny | 25° /8° | 0 mm | 7 | |
| May 12 | Overcast | 27° /11° | 0 mm | 6 | |
| May 13 | Patchy rain possible | 25° /16° | 0.3 mm | 6 | |
| May 14 | Overcast | 27° /16° | 0 mm | 6 | |
| May 15 | Overcast | 31° /18° | 0.3 mm | 7 | |
| May 16 | Moderate rain at times | 27° /14° | 0.7 mm | 6 | |
| May 17 | Overcast | 17° /9° | 0 mm | 4 | |
| May 18 | Overcast | 20° /5° | 0 mm | 5 | |
| May 19 | Patchy rain possible | 17° /9° | 13.1 mm | 4 | |
| May 20 | Moderate or heavy rain shower | 19° /11° | 49.9 mm | 4 | |
| May 21 | Moderate rain at times | 12° /9° | 4.5 mm | 3 | |
| May 22 | Patchy rain possible | 17° /8° | 0.7 mm | 4 | |
| May 23 | Patchy rain possible | 19° /7° | 0.1 mm | 4 | |
| May 24 | Overcast | 19° /11° | 0 mm | 4 | |
| May 25 | Overcast | 14° /11° | 0 mm | 3 | |
| May 26 |  Fog | 18° /8° | 0 mm | 4 | |
| May 27 | Overcast | 20° /12° | 0 mm | 5 | |
| May 28 |  Cloudy | 20° /12° | 0 mm | 5 | |
| May 29 | Fog | 19° /10° | 0 mm | 4 | |
| May 30 | Overcast | 26° /13° | 0 mm | 6 | |
| May 31 |  Thundery outbreaks possible | 29° /13° | 0 mm | 6 | |
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Important Notice
Our weather forecast for Johnson County 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 Johnson County forecast closer to your planned date for the most up-to-date weather information.
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Johnson County in May - FAQ
What are the expected maximum and minimum temperatures in Johnson County during May?
Enjoy moderate daytime temperatures of up to 21° and cooler nights around 10°. Ideal for a range of outdoor activities, from hiking to city tours.
How much rainfall should be expected in Johnson County during May?
Moderate rainfall is anticipated in Johnson County during May, with a total of 79.9 mm spread over approximately 10 days. Considering plans for rainy days is advisable.
What are the typical wind conditions in Johnson County during May?
The average wind speed in Johnson County during May is 20 km/h, suggesting breezy to windy conditions, depending on your activities.
May rainfall patterns in Johnson County
Explore the daily rainfall trends and prepare for Johnson Countys May weather 💧
UV exposure in Johnson County during May
Stay informed about UV levels for safe outdoor activities throughout the month of May ☀️
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Where is Johnson County?Get accurate weather forecasts for Johnson County, located at latitude 41.661 and longitude -91.53. Stay updated with localized weather information tailored for Johnson County.
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