March Weather in Costa Mesa, United States

Last updated: June 24, 2025

In March, the average temperature in Costa Mesa, United States sits at a comfortable 15°C (60°F). Expect a minimum of 7°C (44°F) and a pleasant maximum of 27°C (81°F). Be prepared for precipitation totaling 55 mm (2.2 in) over 8 days, with the average humidity hovering around 75%.

March Temperature in Costa Mesa

In March in Costa Mesa, the average temperature is 15°C (60°F). The maximum can reach 27°C (81°F), and the minimum can be as low as 7°C (44°F). Pack layers for your trip to Costa Mesa to comfortably enjoy the varying temperatures.

March Weather in Costa Mesa: Daily Temperature Highs, Lows, and Averages

The chart illustrates March temperature patterns in Costa Mesa, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Costa Mesa, March typically has an average temperature of 15°C (60°F), with highs reaching up to 27°C (81°F) and lows dropping to around 7°C (44°F).

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

March Precipitation in Costa Mesa

In Costa Mesa in March, the precipitation amount is 55 mm (2.2 in) over the course of 8 days.

March Precipitation Trends in Costa Mesa

The chart displays monthly precipitation patterns in Costa Mesa, with values for each month alongside March’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how March’s conditions compare to those of other months. In Costa Mesa, March typically receives around 55 mm (2.2 inches) of precipitation spread over approximately 8 days.

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

Choose your preferred precipitation unit

Millimeters (mm) Inches (in)

March Humidity in Costa Mesa

In Costa Mesa in March, humidity is 75%. With an average temperature of 15°C (60°F), this humidity feels like a warm, heavy blanket wrapping around you, making outdoor activities slightly uncomfortable and requiring extra hydration while exploring the sights.

March Average Humidity in Costa Mesa

This chart illustrates the average monthly humidity levels in Costa Mesa, with March’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In March, average humidity in Costa Mesa is approximately 75%, offering insight into how humid the weather typically is during this month.

Data source: Humidity data for March generated using information from the Copernicus Climate Change Service.

March UV Index in Costa Mesa

In Costa Mesa in March, the maximum UV index is 8, which corresponds to a very high Exposure Category. This means that the time to burn is only 15 minutes. For more detailed information, you can refer to the Hourly UV Index in Costa Mesa.

Maximum UV Index Levels in Costa Mesa for March

The chart shows the monthly maximum UV Index (UVI) for Costa Mesa in March, 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 March, the maximum UV index in Costa Mesa typically reaches 8, which falls under the very high exposure category.

Data source: Costa Mesa March 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 March Weather in Costa Mesa Compares to Other Months

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

This table compares monthly weather conditions in Costa Mesa, showing how March’s temperature, precipitation, humidity, and UV index levels differ from those of other months.
	Temperature	Precipitation	Humidity	UV
January Weather	14°C (57°F)	65 mm (2.5 inches)	74%	moderate
February Weather	14°C (58°F)	52 mm (2.0 inches)	79%	high
March Weather	15°C (60°F)	55 mm (2.2 inches)	75%	very high
April Weather	17°C (63°F)	23 mm (0.9 inches)	70%	very high
May Weather	18°C (64°F)	12 mm (0.5 inches)	70%	very high
June Weather	20°C (68°F)	4 mm (0.2 inches)	72%	extreme
July Weather	22°C (72°F)	3 mm (0.1 inches)	73%	extreme
August Weather	23°C (73°F)	2 mm (0.1 inches)	69%	very high
September Weather	22°C (72°F)	3 mm (0.1 inches)	68%	very high
October Weather	20°C (69°F)	9 mm (0.4 inches)	67%	high
November Weather	17°C (63°F)	18 mm (0.7 inches)	68%	moderate
December Weather	14°C (58°F)	68 mm (2.7 inches)	71%	moderate