May Weather in Simi Valley, United States

Last updated: June 24, 2025

In May, the average temperature in Simi Valley, United States hovers around 17°C (64°F). Expect a minimum of 8°C (46°F) and a maximum of 33°C (92°F), providing a delightful range for your activities. During this month, precipitation averages about 15 mm (0.6 in) over the span of 2 days, while the average humidity remains comfortable at 57%. Embrace the pleasant climate!

May Temperature in Simi Valley

In May in Simi Valley, the average temperature is 17°C (64°F). Maximums can reach 33°C (92°F), while minimums can be as low as 8°C (46°F). This makes it an ideal time for travelers to enjoy mild weather with the possibility of both warm and cooler days.

May Weather in Simi Valley: Daily Temperature Highs, Lows, and Averages

The chart illustrates May temperature patterns in Simi Valley, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Simi Valley, May typically has an average temperature of 17°C (64°F), with highs reaching up to 33°C (92°F) and lows dropping to around 8°C (46°F).

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

May Precipitation in Simi Valley

In Simi Valley in May, the precipitation amount is 15 mm (0.6 in) over the course of 2 days.

May Precipitation Trends in Simi Valley

The chart displays monthly precipitation patterns in Simi Valley, 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 Simi Valley, May typically receives around 15 mm (0.6 inches) of precipitation spread over approximately 2 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 Simi Valley

In Simi Valley in May, humidity is 57%. With an average temperature of 17°C (64°F), this humidity feels like a refreshing embrace, making it quite pleasant for traveling as long as you stay hydrated and enjoy the mild air.

May Average Humidity in Simi Valley

This chart illustrates the average monthly humidity levels in Simi Valley, 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 Simi Valley is approximately 57%, 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 Simi Valley

In Simi Valley in May, the maximum UV index reaches 11, which corresponds to an extreme Exposure Category. With a time to burn of just 10 minutes, it's essential to take precautions. For more details, you can check the Hourly UV Index in Simi Valley.

Maximum UV Index Levels in Simi Valley for May

The chart shows the monthly maximum UV Index (UVI) for Simi Valley 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 Simi Valley typically reaches 11, which falls under the extreme exposure category.

Data source: Simi Valley 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 Simi Valley Compares to Other Months

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

This table compares monthly weather conditions in Simi Valley, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	13°C (55°F)	79 mm (3.1 inches)	78%	moderate
February Weather	13°C (55°F)	63 mm (2.5 inches)	82%	high
March Weather	14°C (57°F)	80 mm (3.2 inches)	75%	very high
April Weather	17°C (62°F)	20 mm (0.8 inches)	68%	very high
May Weather	17°C (64°F)	15 mm (0.6 inches)	57%	extreme
June Weather	20°C (69°F)	2 mm (0.1 inches)	52%	extreme
July Weather	23°C (74°F)	1 mm (0.0 inches)	46%	extreme
August Weather	24°C (75°F)	1 mm (0.0 inches)	39%	extreme
September Weather	22°C (73°F)	2 mm (0.1 inches)	48%	very high
October Weather	20°C (68°F)	10 mm (0.4 inches)	59%	high
November Weather	16°C (62°F)	19 mm (0.7 inches)	72%	moderate
December Weather	12°C (55°F)	86 mm (3.4 inches)	76%	moderate