May Weather in Union, United States

Last updated: June 24, 2025

In Union, United States, the average temperature in May hovers around 22°C (72°F). Expect temperatures to range from a brisk 6°C (43°F) at their lowest to a sweltering 36°C (98°F) at their peak. During this month, you can anticipate approximately 115 mm (4.5 in) of precipitation spread over 11 days, contributing to an average humidity of 83%.

May Temperature in Union

In May in Union, the average temperature is 22°C (72°F). Maximums can reach 36°C (98°F), while minimums can dip as low as 6°C (43°F). This diverse range of temperatures makes it essential for travelers to pack both warm and light clothing for their visit.

May Weather in Union: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Union, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Union, May typically has an average temperature of 22°C (72°F), with highs reaching up to 36°C (98°F) and lows dropping to around 6°C (43°F).

Data source: Temperature data for Union generated using information from the Copernicus Climate Change Service.

May Precipitation in Union

In Union in May, the total precipitation amount is 115 mm (4.5 in) spread over 11 days.

May Precipitation Trends in Union

The chart displays monthly precipitation patterns in Union, with values for each month alongside May’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how May’s conditions compare to those of other months. In Union, May typically receives around 115 mm (4.5 inches) of precipitation spread over approximately 11 days.

Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.

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Millimeters (mm) Inches (in)

May Humidity in Union

In Union in May humidity is 83%. With average temperature 22°C (72°F), this humidity feels like a heavy blanket wrapping around you, making outdoor activities challenging and prompting travelers to seek shade or frequent stops for hydration.

May Average Humidity in Union

This chart illustrates the average monthly humidity levels in Union, with May’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In May, average humidity in Union is approximately 83%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Union

In Union in May, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Union.

Maximum UV Index Levels in Union for May

The chart shows the monthly maximum UV Index (UVI) for Union in May, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In May, the maximum UV index in Union typically reaches 11, which falls under the extreme exposure category.

Data source: Union May UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

Extreme (11+): Avoid the sun, stay in shade.
Very High (8-10): Limit sun exposure.
High (6-7): Use SPF 30+ and protective clothing.
Moderate (3-5): Midday shade recommended.
Low (0-2): No protection needed.

How May Weather in Union Compares to Other Months

Weather in Union varies notably across the year, with each month offering distinct climate conditions. This page compares May’s weather to other months in Union, focusing on differences in temperature, rainfall, humidity, and UV levels.

This table compares monthly weather conditions in Union, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	8°C (46°F)	95 mm (3.7 inches)	86%	moderate
February Weather	10°C (51°F)	123 mm (4.8 inches)	85%	high
March Weather	13°C (56°F)	90 mm (3.6 inches)	84%	very high
April Weather	17°C (63°F)	108 mm (4.2 inches)	82%	very high
May Weather	22°C (72°F)	115 mm (4.5 inches)	83%	extreme
June Weather	25°C (77°F)	90 mm (3.5 inches)	82%	extreme
July Weather	27°C (81°F)	113 mm (4.5 inches)	80%	extreme
August Weather	26°C (79°F)	127 mm (5.0 inches)	74%	very high
September Weather	24°C (76°F)	115 mm (4.5 inches)	75%	very high
October Weather	19°C (67°F)	97 mm (3.8 inches)	79%	very high
November Weather	11°C (53°F)	96 mm (3.8 inches)	87%	high
December Weather	9°C (49°F)	130 mm (5.1 inches)	87%	moderate