The best times to visit Costa Mesa for ideal weather are
March 12th to November 25th
based on average temperature and humidity from NOAA (the National Oceanic and Atmospheric Administration). Read below for more weather and travel details.
Costa Mesa Travel Guide
Other Costa Mesa Travel Info
Weather in Costa Mesa
Average temperatures in Costa Mesa vary somewhat. Considering humidity, temperatures feel very enjoyable all year with a very low chance of rain or snow throughout the year. The area is more temperate than most — in the 88th percentile for pleasant weather — compared to tourist destinations worldwide. Weeks with ideal weather are listed above. If you’re looking for the very warmest time to visit Costa Mesa, the hottest months are September, August, and then July. See average monthly temperatures below. The warmest time of year is generally late August to early September where highs are regularly around 85.8°F (29.9°C) with temperatures rarely dropping below 68°F (20°C) at night.
Costa Mesa Temperatures (Fahrenheit)
Costa Mesa Temperatures (Celsius)
The way we experience weather isn’t all about temperature. Higher temperatures affect us much more at higher humidity, and colder temperatures feel piercing with high winds. Our perceived temperatures factor in humidity and wind chill to better represent how hot or cold the day feels to a person.
Costa Mesa Perceived Temperature (F)
Costa Mesa Perceived Temperature (C)
Average Costa Mesa Temperatures by Month
Daily highs (averaged for the month) usually give the best indication of the weather. A significantly lower mean and low generally just means it gets colder at night.
|Month||Avg. High (°F)||Avg. Mean (°F)||Avg. Low (°F)|
|Month||Avg. High (°C)||Avg. Mean (°C)||Avg. Low (°C)|
Precipitation (Rain or Snow)
If dry weather is what you’re after, the months with the lowest chance of significant precipitation in Costa Mesa are June, August, and then September. Note that we define “significant precipitation” as .1 inches or more in this section. The lowest chance of rain or snow occurs around late May. For example, on the week of May 21st there are no days of precipitation on average. By contrast, it’s most likely to rain or snow in late January with an average of 2 days of significant precipitation the week of January 22nd.
When can you find snow in Costa Mesa? Weather stations report no annual snow. Please note that a value of 0 for snow in the graph below may either mean there was no snow, or that snow is unreported.
Chance of Precipitation
The graph below shows the % chance of rainy and snowy days in Costa Mesa.
Snow on the Ground
The graph below shows the average snow on the ground in Costa Mesa (in).
Average Rain and Snow by Month
|Month||Daily Chance of Rain||Average Snow Depth (in)||Total Precipitation (in)|
|Month||Daily Chance of Rain||Average Snow Depth (cm)||Total Precipitation (cm)|
Humidity and Wind
Costa Mesa has some slightly muggy months, with moderately humid months on the other side of the year. The least humid month is January (44.8% relative humidity), and the most humid month is June (61.3%).
Wind in Costa Mesa is usually extremely calm. The windiest month is May, followed by June and July. May’s average wind speed of around 5.1 knots (5.8 MPH or 9.4 KPH) is considered “a light breeze.” Maximum sustained winds (the highest speed for the day lasting more than a few moments) are at their highest in early May where average top sustained speeds reach 11.6 knots, which is considered a moderate breeze.
Relative Humidity (%)
The graph below shows the average % humidity by month in Costa Mesa.
The graph below shows wind speed (max and average) in knots.
Average Wind Speeds
Show Wind Speeds
All wind speeds are in knots. 1 knot = 1.15 MPH or 1.85 KPH.
|Month||Avg. Wind||Avg. Wind Feel||Sustained High Wind||High Wind Feel|
|Jan||3.1||Barely noticeable||9.4||Gentle breeze|
|Feb||3.5||Barely noticeable||9.9||Gentle breeze|
|Mar||4||Light breeze||10.5||Gentle breeze|
|Apr||4.7||Light breeze||11.1||Significant breeze|
|May||5.1||Light breeze||10.9||Gentle breeze|
|Jun||5||Light breeze||10.5||Gentle breeze|
|Jul||4.7||Light breeze||10.3||Gentle breeze|
|Aug||4.3||Light breeze||9.8||Gentle breeze|
|Sep||3.8||Barely noticeable||9.4||Gentle breeze|
|Oct||3.3||Barely noticeable||9.3||Gentle breeze|
|Nov||2.7||Barely noticeable||8.7||Gentle breeze|
|Dec||2.9||Barely noticeable||9||Gentle breeze|
Show Relative Humidity by Month
|Month||Avg. Relative Humidity|
Is it Safe to Travel to Costa Mesa?
Our best data indicates this area is generally safe. As of Oct 07, 2019 there are no travel advisories or warnings for the United States; exercise normal security precautions. Check this page for any recent changes or regions to avoid: Travel Advice and Advisories. This advisory was last updated on Sep 23, 2019.
The Busiest and Least Crowded Months
The busiest month for tourism in Costa Mesa, CA, US is July, followed by June and March. Prices for hotels and flights will be most expensive during these months, though you can save if you purchase well in advance. Tourists are unlikely to visit Costa Mesa in December. Those willing to visit at these times will likely find it the least expensive month.
Estimated Tourism by Month
Most Popular Months to Visit
Overall Costa Mesa Travel Experience by Season
Spring (March through May)
Humidity and temperatures combine to make this season feel moderate. Highs range from 75.8°F (24.3°C) and 68.8°F (20.4°C) with warmer temperatures in the later months. Rain is rare with 1 to 2 days of significant precipitation per month. Spring is the second busiest for tourism, which makes it a good time for those looking for things to do.
Summer (June through August)
The middle-year months have very comfortable weather with high temperatures that are comfortable. These months see the least precipitation with 0 to 1 days of precipitation per month. June – August is the busiest season for tourism in Costa Mesa, so lodging and other accommodations may cost more than usual.
Fall (September through November)
Fall daily highs range from 85°F (29.4°C) and 71.9°F (22.2°C), which will feel very nice given the humidity and wind. It rains or snows a normal amount: 0 to 2 days per month. Tourism is fairly slow during these months due to the weather, so hotels may be lower priced.
Winter (December through February)
Weather is somewhat cool this time of year in Costa Mesa to be enjoyable for warm weather travelers. The average high during this season is between 71.9°F (22.2°C) and 65.7°F (18.7°C). On average, it rains or snows a smalll amount: 3 to 5 times per month. These times of year are the slowest with tourists.