May Weather in Castaic, United States

Last updated: June 24, 2025

In Castaic, United States, the average temperature in May hovers around 18°C (65°F). While you can expect a comfortable climate, temperatures can vary significantly, with a minimum of 6°C (43°F) and a maximum of 34°C (93°F). Rainfall is moderate, with approximately 16 mm (0.6 in) of precipitation spread over 3 days. Additionally, the average humidity sits at 57%, contributing to a pleasant, mild atmosphere.

May Temperature in Castaic

In May in Castaic, the average temperature is 18°C (65°F), with maximums reaching 34°C (93°F) and minimums dropping to as low as 6°C (43°F). This makes it an ideal time for travelers to experience a comfortable climate while exploring the local attractions.

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

The chart illustrates May temperature patterns in Castaic, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Castaic, May typically has an average temperature of 18°C (65°F), with highs reaching up to 34°C (93°F) and lows dropping to around 6°C (43°F).

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

May Precipitation in Castaic

In Castaic in May, the precipitation amount is 16 mm (0.6 in), spread over a duration of 3 days.

May Precipitation Trends in Castaic

The chart displays monthly precipitation patterns in Castaic, 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 Castaic, May typically receives around 16 mm (0.6 inches) of precipitation spread over approximately 3 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 Castaic

In Castaic in May, humidity is 57%. With an average temperature of 18°C (65°F), this humidity feels like a refreshing yet slightly sticky embrace, making it perfect for outdoor excursions but requiring a bit of extra care to stay comfortable while exploring.

May Average Humidity in Castaic

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

In Castaic 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 Castaic.

Maximum UV Index Levels in Castaic for May

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

Data source: Castaic 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 Castaic Compares to Other Months

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

This table compares monthly weather conditions in Castaic, showing how May’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	10°C (51°F)	63 mm (2.5 inches)	78%	moderate
February Weather	11°C (52°F)	55 mm (2.2 inches)	82%	high
March Weather	12°C (55°F)	71 mm (2.8 inches)	75%	very high
April Weather	16°C (62°F)	22 mm (0.9 inches)	68%	very high
May Weather	18°C (65°F)	16 mm (0.6 inches)	57%	extreme
June Weather	22°C (72°F)	3 mm (0.1 inches)	52%	extreme
July Weather	25°C (78°F)	1 mm (0.1 inches)	46%	extreme
August Weather	26°C (78°F)	2 mm (0.1 inches)	39%	extreme
September Weather	23°C (74°F)	4 mm (0.2 inches)	48%	very high
October Weather	19°C (66°F)	9 mm (0.3 inches)	59%	high
November Weather	15°C (59°F)	19 mm (0.7 inches)	72%	moderate
December Weather	10°C (51°F)	68 mm (2.7 inches)	76%	moderate