May Weather in Grafton, United States

Last updated: June 24, 2025

In May, the average temperature in Grafton, United States hovers around 13°C (56°F). Temperature ranges can be quite diverse, with a minimum dipping to -1°C (31°F) and a maximum soaring to 33°C (91°F). Expect about 83 mm (3.3 in) of precipitation over 12 days, contributing to an average humidity level of 72%.

May Temperature in Grafton

In May in Grafton, the average temperature is 13°C (56°F), with maximums reaching up to 33°C (91°F) and minimums plummeting as low as -1°C (31°F). Travelers should pack for a wide range of temperatures, from warm afternoons to chilly evenings.

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

The chart illustrates May temperature patterns in Grafton, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Grafton, May typically has an average temperature of 13°C (56°F), with highs reaching up to 33°C (91°F) and lows dropping to around -1°C (31°F).

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

May Precipitation in Grafton

In Grafton in May, the precipitation amount is 83 mm (3.3 in) distributed over the course of 12 days.

May Precipitation Trends in Grafton

The chart displays monthly precipitation patterns in Grafton, 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 Grafton, May typically receives around 83 mm (3.3 inches) of precipitation spread over approximately 12 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 Grafton

In Grafton in May, humidity is 72%. With an average temperature of 13°C (56°F), this humidity feels like a damp blanket enveloping you, making outdoor activities somewhat uncomfortable and reminding travelers to stay hydrated and seek shade whenever possible.

May Average Humidity in Grafton

This chart illustrates the average monthly humidity levels in Grafton, 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 Grafton is approximately 72%, 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 Grafton

In Grafton 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 Grafton.

Maximum UV Index Levels in Grafton for May

The chart shows the monthly maximum UV Index (UVI) for Grafton 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 Grafton typically reaches 9, which falls under the very high exposure category.

Data source: Grafton 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 Grafton Compares to Other Months

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

This table compares monthly weather conditions in Grafton, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-6°C (22°F)	70 mm (2.8 inches)	86%	moderate
February Weather	-4°C (25°F)	82 mm (3.2 inches)	84%	moderate
March Weather	0°C (32°F)	75 mm (2.9 inches)	82%	moderate
April Weather	6°C (44°F)	121 mm (4.8 inches)	80%	very high
May Weather	13°C (56°F)	83 mm (3.3 inches)	72%	very high
June Weather	19°C (66°F)	91 mm (3.6 inches)	72%	very high
July Weather	22°C (71°F)	125 mm (4.9 inches)	67%	very high
August Weather	21°C (69°F)	89 mm (3.5 inches)	66%	very high
September Weather	17°C (62°F)	65 mm (2.6 inches)	71%	high
October Weather	10°C (50°F)	129 mm (5.1 inches)	78%	moderate
November Weather	2°C (36°F)	106 mm (4.2 inches)	84%	moderate
December Weather	-3°C (26°F)	109 mm (4.3 inches)	81%	low