nomadseason

May Weather in Lewistown, United States

Last updated: June 24, 2025

In May, the average temperature in Lewistown, United States hovers around 10°C (50°F). However, be prepared for a range of temperatures, with minimums dipping to -6°C (21°F) and maximums soaring to 27°C (81°F). Expect a total precipitation of 84 mm (3.3 in) across roughly 16 days, contributing to an average humidity of 75%.

May Temperature in Lewistown

In May in Lewistown, the average temperature is 10°C (50°F), with maximums reaching 27°C (81°F) and minimums dropping as low as -6°C (21°F). This variation in temperature makes it essential for travelers to pack layers to stay comfortable throughout the day.

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

The chart illustrates May temperature patterns in Lewistown, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Lewistown, May typically has an average temperature of 10°C (50°F), with highs reaching up to 27°C (81°F) and lows dropping to around -6°C (21°F).
JanFebMarAprMayJunJulAugSepOctNovDec251832385060696757413426
Data source: Temperature data for Lewistown generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

May Precipitation in Lewistown

In Lewistown in May, the total precipitation amount is 84 mm (3.3 in) spread over 16 days.

May Precipitation Trends in Lewistown

The chart displays monthly precipitation patterns in Lewistown, 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 Lewistown, May typically receives around 84 mm (3.3 inches) of precipitation spread over approximately 16 days.
JanFebMarAprMayJunJulAugSepOctNovDec254329768480303145453431
Data source: Precipitation data for May generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

May Humidity in Lewistown

In Lewistown in May humidity is 75%. With an average temperature of 10°C (50°F), this humidity feels like a damp chill that seeps into your bones, making outdoor exploration uncomfortable and necessitating extra layers for warmth and comfort.

May Average Humidity in Lewistown

This chart illustrates the average monthly humidity levels in Lewistown, 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 Lewistown is approximately 75%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec81%85%77%72%75%78%79%76%67%69%78%85%
Data source: Humidity data for May generated using information from the Copernicus Climate Change Service.

May UV Index in Lewistown

In Lewistown 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 Lewistown.

Maximum UV Index Levels in Lewistown for May

The chart shows the monthly maximum UV Index (UVI) for Lewistown 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 Lewistown typically reaches 9, which falls under the very high exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec24589101098532
Data source: Lewistown 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 Lewistown Compares to Other Months

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

This table compares monthly weather conditions in Lewistown, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
 TemperaturePrecipitationHumidityUV
January Weather-4°C (25°F)25 mm (1.0 inches)81%low
February Weather-8°C (18°F)43 mm (1.7 inches)85%moderate
March Weather0°C (32°F)29 mm (1.2 inches)77%moderate
April Weather3°C (38°F)76 mm (3.0 inches)72%very high
May Weather10°C (50°F)84 mm (3.3 inches)75%very high
June Weather16°C (61°F)80 mm (3.2 inches)78%very high
July Weather20°C (69°F)30 mm (1.2 inches)79%very high
August Weather19°C (67°F)31 mm (1.2 inches)76%very high
September Weather14°C (57°F)45 mm (1.8 inches)67%very high
October Weather5°C (42°F)45 mm (1.8 inches)69%moderate
November Weather1°C (34°F)34 mm (1.3 inches)78%moderate
December Weather-3°C (27°F)31 mm (1.2 inches)85%low

Compare Lewistown's Climate with Cities Worldwide