May Weather in Hillsboro, United States

Last updated: June 24, 2025

In Hillsboro, United States, the average temperature in May hovers around 15°C (59°F). However, prepare for a range of conditions: temperatures can dip to a chilly -1°C (31°F) or soar to a sizzling 34°C (93°F). Rainfall is frequent with an average precipitation of 137 mm (5.4 in) over 14 days, and humidity remains high at 75%. Dress accordingly and enjoy the diverse climate!

May Temperature in Hillsboro

In May in Hillsboro, the average temperature is 15°C (59°F), with maximums reaching up to 34°C (93°F) and minimums dropping as low as -1°C (31°F). This suggests that travelers should be prepared for a wide range of weather conditions during their visit.

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

The chart illustrates May temperature patterns in Hillsboro, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Hillsboro, May typically has an average temperature of 15°C (59°F), with highs reaching up to 34°C (93°F) and lows dropping to around -1°C (31°F).

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

May Precipitation in Hillsboro

In Hillsboro in May, the precipitation amount is 137 mm (5.4 in) spread over 14 days.

May Precipitation Trends in Hillsboro

The chart displays monthly precipitation patterns in Hillsboro, 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 Hillsboro, May typically receives around 137 mm (5.4 inches) of precipitation spread over approximately 14 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 Hillsboro

In Hillsboro in May, humidity is 75%. With an average temperature of 15°C (59°F), this humidity feels like a warm blanket enveloping you, making it feel more oppressive than refreshing, which can be a challenge for travelers seeking comfort while exploring the area.

May Average Humidity in Hillsboro

This chart illustrates the average monthly humidity levels in Hillsboro, 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 Hillsboro is approximately 75%, 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 Hillsboro

In Hillsboro 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 Hillsboro.

Maximum UV Index Levels in Hillsboro for May

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

Data source: Hillsboro 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 Hillsboro Compares to Other Months

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

This table compares monthly weather conditions in Hillsboro, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-7°C (20°F)	41 mm (1.6 inches)	84%	low
February Weather	-6°C (21°F)	54 mm (2.1 inches)	85%	moderate
March Weather	1°C (35°F)	59 mm (2.3 inches)	84%	moderate
April Weather	7°C (45°F)	91 mm (3.6 inches)	83%	very high
May Weather	15°C (59°F)	137 mm (5.4 inches)	75%	very high
June Weather	21°C (70°F)	119 mm (4.7 inches)	79%	very high
July Weather	23°C (74°F)	107 mm (4.2 inches)	75%	very high
August Weather	21°C (70°F)	116 mm (4.6 inches)	69%	very high
September Weather	18°C (64°F)	110 mm (4.3 inches)	74%	very high
October Weather	10°C (50°F)	111 mm (4.4 inches)	79%	moderate
November Weather	2°C (35°F)	51 mm (2.0 inches)	88%	moderate
December Weather	-3°C (27°F)	46 mm (1.8 inches)	82%	low