May Weather in Perth, Canada

Last updated: June 18, 2025

In May, the average temperature in Perth, Canada is a comfortable 12°C (55°F). Visitors can expect a range from a chilly minimum of -3°C (27°F) to a warm maximum of 31°C (88°F). During this month, precipitation typically amounts to 102 mm (4.0 in) over 12 days, while the average humidity hovers around 75%, ensuring a pleasantly moist atmosphere.

May Temperature in Perth

In May in Perth, the average temperature is 12°C (55°F). Maximums can reach 31°C (88°F), while minimums can drop as low as -3°C (27°F). Be prepared for fluctuating temperatures and pack accordingly for your travels.

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

The chart illustrates May temperature patterns in Perth, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Perth, May typically has an average temperature of 12°C (55°F), with highs reaching up to 31°C (88°F) and lows dropping to around -3°C (27°F).

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

May Precipitation in Perth

In Perth in May, the total precipitation amount is 102 mm (4.0 in), occurring over a span of 12 days.

May Precipitation Trends in Perth

The chart displays monthly precipitation patterns in Perth, 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 Perth, May typically receives around 102 mm (4.0 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 Perth

In Perth in May humidity is 75%. With an average temperature of 12°C (55°F), this humidity feels like a damp blanket wrapping around you, making travel slightly uncomfortable as the chill magnifies the moisture in the air.

May Average Humidity in Perth

This chart illustrates the average monthly humidity levels in Perth, 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 Perth 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 Perth

In Perth 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 Perth.

Maximum UV Index Levels in Perth for May

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

Data source: Perth 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 Perth Compares to Other Months

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

This table compares monthly weather conditions in Perth, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	-8°C (18°F)	72 mm (2.8 inches)	93%	low
February Weather	-7°C (20°F)	72 mm (2.8 inches)	93%	moderate
March Weather	-2°C (29°F)	75 mm (2.9 inches)	86%	moderate
April Weather	5°C (42°F)	115 mm (4.5 inches)	82%	very high
May Weather	12°C (55°F)	102 mm (4.0 inches)	75%	very high
June Weather	18°C (64°F)	85 mm (3.3 inches)	68%	very high
July Weather	21°C (71°F)	107 mm (4.2 inches)	69%	very high
August Weather	20°C (69°F)	87 mm (3.4 inches)	67%	very high
September Weather	16°C (61°F)	55 mm (2.2 inches)	72%	high
October Weather	10°C (49°F)	126 mm (5.0 inches)	83%	moderate
November Weather	1°C (35°F)	89 mm (3.5 inches)	88%	moderate
December Weather	-4°C (25°F)	76 mm (3.0 inches)	89%	low