May Weather in Harrisburg, United States

Last updated: June 24, 2025

In Harrisburg, United States, the average temperature in May hovers around 13°C (55°F), with a range that can dip to a chilly -2°C (28°F) and soar up to a warm 31°C (88°F). Expect about 117 mm (4.6 in) of precipitation spread over 14 days, accompanied by an average humidity of 74%. Plan accordingly for a mix of conditions!

May Temperature in Harrisburg

In May in Harrisburg, the average temperature is 13°C (55°F). Maximums can reach 31°C (88°F) and minimums can drop as low as -2°C (28°F). This makes it essential to pack for both warm days and chilly nights when traveling to Harrisburg during this time.

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

The chart illustrates May temperature patterns in Harrisburg, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Harrisburg, May typically has an average temperature of 13°C (55°F), with highs reaching up to 31°C (88°F) and lows dropping to around -2°C (28°F).

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

May Precipitation in Harrisburg

In Harrisburg in May, the precipitation amount is 117 mm (4.6 in) spread over 14 days.

May Precipitation Trends in Harrisburg

The chart displays monthly precipitation patterns in Harrisburg, 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 Harrisburg, May typically receives around 117 mm (4.6 inches) of precipitation spread over approximately 14 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

May Humidity in Harrisburg

In Harrisburg in May, humidity is 74%. With an average temperature of 13°C (55°F), this humidity feels like a damp blanket wrapping around you, making outdoor activities somewhat uncomfortable and demanding frequent breaks in shaded areas.

May Average Humidity in Harrisburg

This chart illustrates the average monthly humidity levels in Harrisburg, 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 Harrisburg is approximately 74%, 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 Harrisburg

In Harrisburg 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 Harrisburg.

Maximum UV Index Levels in Harrisburg for May

The chart shows the monthly maximum UV Index (UVI) for Harrisburg 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 Harrisburg typically reaches 10, which falls under the very high exposure category.

Data source: Harrisburg 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 Harrisburg Compares to Other Months

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

This table compares monthly weather conditions in Harrisburg, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	0°C (32°F)	14 mm (0.6 inches)	72%	moderate
February Weather	-2°C (30°F)	23 mm (0.9 inches)	76%	moderate
March Weather	5°C (40°F)	67 mm (2.7 inches)	61%	high
April Weather	8°C (46°F)	53 mm (2.1 inches)	60%	very high
May Weather	13°C (55°F)	117 mm (4.6 inches)	74%	very high
June Weather	21°C (69°F)	57 mm (2.2 inches)	82%	extreme
July Weather	24°C (75°F)	46 mm (1.8 inches)	82%	extreme
August Weather	22°C (73°F)	35 mm (1.4 inches)	84%	very high
September Weather	19°C (66°F)	24 mm (1.0 inches)	75%	very high
October Weather	9°C (48°F)	36 mm (1.4 inches)	73%	high
November Weather	5°C (42°F)	25 mm (1.0 inches)	74%	moderate
December Weather	1°C (35°F)	18 mm (0.7 inches)	77%	moderate