Last updated: June 24, 2025
In May, the average temperature in Mason City, United States is a pleasant 18°C (65°F), though it can dip as low as 0°C (33°F) or soar to a sweltering 35°C (95°F). Expect around 156 mm (6.1 in) of precipitation spread over 15 days, resulting in an average humidity of 79%. Whether you're basking in the warmth or dodging the rain, prepare for a unique climate experience!
In May in Mason City, the average temperature is 18°C (65°F), with maximums reaching up to 35°C (95°F) and minimums dipping as low as 0°C (33°F). This makes it an ideal time for travelers to enjoy a variety of outdoor activities while being prepared for a range of temperatures.
In Mason City in May, the total precipitation amount is 156 mm (6.1 in) distributed over 15 days.
In Mason City in May, humidity is 79%. With an average temperature of 18°C (65°F), this humidity feels like walking through a warm mist, making traveling slightly uncomfortable and sticky, but offering a refreshing escape when you find moments of shade or a breeze.
In Mason City in May, the maximum UV index reaches 10, which corresponds to a very high Exposure Category. With a time to burn of just 15 minutes, it's crucial to take precautions. For more detailed information, you can check the Hourly UV Index in Mason City.
UV Risk Categories
Weather in Mason City varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Mason City, focusing on differences in temperature, rainfall, humidity, and UV levels.
| Temperature | Precipitation | Humidity | UV | |
|---|---|---|---|---|
| January Weather | -2°C (28°F) | 66 mm (2.6 inches) | 82% | moderate |
| February Weather | -1°C (31°F) | 67 mm (2.7 inches) | 83% | moderate |
| March Weather | 6°C (43°F) | 123 mm (4.8 inches) | 84% | high |
| April Weather | 11°C (52°F) | 120 mm (4.7 inches) | 85% | very high |
| May Weather | 18°C (65°F) | 156 mm (6.1 inches) | 79% | very high |
| June Weather | 24°C (75°F) | 136 mm (5.4 inches) | 82% | extreme |
| July Weather | 25°C (78°F) | 117 mm (4.6 inches) | 80% | very high |
| August Weather | 24°C (75°F) | 97 mm (3.8 inches) | 81% | very high |
| September Weather | 21°C (71°F) | 68 mm (2.7 inches) | 80% | very high |
| October Weather | 14°C (57°F) | 114 mm (4.5 inches) | 82% | high |
| November Weather | 5°C (42°F) | 63 mm (2.5 inches) | 88% | moderate |
| December Weather | 2°C (36°F) | 53 mm (2.1 inches) | 84% | low |