May Weather in Union, United States

Last updated: June 24, 2025

In May, the average temperature in Union, United States hovers around 15°C (60°F), with temperatures ranging from a chilly -2°C (29°F) to a warm 33°C (92°F). Expect wet conditions, as 162 mm (6.4 in) of precipitation can be expected over 14 days, accompanied by an average humidity of 78%. Stay prepared for a mix of weather while enjoying the vibrancy of this beautiful location!

May Temperature in Union

In May in Union, the average temperature is 15°C (60°F), with a maximum that can reach 33°C (92°F) and a minimum as low as -2°C (29°F). It's advisable to pack layers to accommodate the wide range of temperatures during your 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 15°C (60°F), with highs reaching up to 33°C (92°F) and lows dropping to around -2°C (29°F).
JanFebMarAprMayJunJulAugSepOctNovDec232538476071757266533731
Data source: Temperature data for Union generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Union

In Union in May, the total precipitation amount is 162 mm (6.4 in) over the course of 14 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 162 mm (6.4 inches) of precipitation spread over approximately 14 days.
JanFebMarAprMayJunJulAugSepOctNovDec6159721121621199292991215153
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
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May Humidity in Union

In Union in May, humidity is 78%. With an average temperature of 15°C (60°F), this humidity feels like a warm, damp embrace that can make outdoor activities a bit uncomfortable, highlighting the importance of staying hydrated and taking breaks in the shade while exploring.

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 78%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec85%85%85%85%78%80%78%76%79%83%88%82%
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 is 9, which corresponds to a very high Exposure Category. The time to burn is just 15 minutes, so it's essential to take precautions. For detailed information, 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 9, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec34689101098532
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.
 TemperaturePrecipitationHumidityUV
January Weather-5°C (23°F)61 mm (2.4 inches)85%moderate
February Weather-4°C (26°F)59 mm (2.3 inches)85%moderate
March Weather3°C (38°F)72 mm (2.8 inches)85%high
April Weather8°C (47°F)112 mm (4.4 inches)85%very high
May Weather15°C (60°F)162 mm (6.4 inches)78%very high
June Weather21°C (71°F)119 mm (4.7 inches)80%very high
July Weather24°C (75°F)92 mm (3.6 inches)78%very high
August Weather22°C (72°F)92 mm (3.6 inches)76%very high
September Weather19°C (67°F)99 mm (3.9 inches)79%very high
October Weather11°C (53°F)121 mm (4.8 inches)83%moderate
November Weather3°C (38°F)51 mm (2.0 inches)88%moderate
December Weather0°C (32°F)53 mm (2.1 inches)81%low

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