Weather forecast for 10 daysCosta Mesa, CA
Weather forecast for the weekend
Sunday Oct 18, 2026
- 82°F
- 64°F
Sunny
- Precip. probability: 0%
- Precipitation: 0"
- Wind: 10mphSW 234°
- Humidity: 41%
- UV index: 6
- Sunrise: 6:59 am PDT
- Sunset: 6:14 pm PDT
- details ▼
On Sunday, October 18, conditions remain stable and sunny, with little cloud presence.
The temperature is anticipated to vary between a warm 82.4°F and an enjoyable 64.4°F.
The maximum heat index, which factors the actual air temperature with the relative humidity, is evaluated at 82.4°F.
A high of 82.4°F is expected, which resembles September's climate average of 76.1°F more than October's 73°F.
Sunrise will be at 6:59 am and sunset at 6:14 pm; tomorrow's daylight will last for 11h and 16min.
The temperature is anticipated to vary between a warm 82.4°F and an enjoyable 64.4°F.
The maximum heat index, which factors the actual air temperature with the relative humidity, is evaluated at 82.4°F.
A high of 82.4°F is expected, which resembles September's climate average of 76.1°F more than October's 73°F.
Sunrise will be at 6:59 am and sunset at 6:14 pm; tomorrow's daylight will last for 11h and 16min.
10-day overview
Daily temperatures
Warmest day: tomorrow 82°C.
Coldest day: Thursday 68°C.
Coldest day: Thursday 68°C.
Chance of precipitation
Highest chance: Thursday 73%.
Long-term weather forecast
- Saturday
- Oct 17, 2026
- min.
- 68°F
Partly Cloudy
- Precip. probability: 1%
- Precipitation: 0"
- Wind: 9mphE 89°
- Humidity: 49%
- UV index: 0
- Sunrise: 6:58 am PDT
- Sunset: 6:15 pm PDT
- details ▼
- Sunday
- Oct 18, 2026
- 82°F
- 64°F
Sunny
- Precip. probability: 0%
- Precipitation: 0"
- Wind: 10mphSW 234°
- Humidity: 41%
- UV index: 6
- Sunrise: 6:59 am PDT
- Sunset: 6:14 pm PDT
- details ▼
- Monday
- Oct 19, 2026
- 81°F
- 66°F
Partly Cloudy
- Precip. probability: 19%
- Precipitation: 0"
- Wind: 9mphS 182°
- Humidity: 63%
- UV index: 6
- Sunrise: 6:59 am PDT
- Sunset: 6:13 pm PDT
- details ▼
- Tuesday
- Oct 20, 2026
- 77°F
- 64°F
Partly Cloudy
- Precip. probability: 6%
- Precipitation: 0"
- Wind: 9mphS 176°
- Humidity: 68%
- UV index: 6
- Sunrise: 7:00 am PDT
- Sunset: 6:12 pm PDT
- details ▼
- Wednesday
- Oct 21, 2026
- 75°F
- 64°F
Showers
- Precip. probability: 64%
- Precipitation: 0.43"
- Wind: 12mphSSE 163°
- Humidity: 67%
- UV index: 5
- Sunrise: 7:01 am PDT
- Sunset: 6:10 pm PDT
- details ▼
- Thursday
- Oct 22, 2026
- 68°F
- 61°F
Thunderstorms
- Precip. probability: 73%
- Precipitation: 0.24"
- Wind: 9mphSSW 192°
- Humidity: 69%
- UV index: 5
- Sunrise: 7:02 am PDT
- Sunset: 6:09 pm PDT
- details ▼
- Friday
- Oct 23, 2026
- 73°F
- 61°F
Partly Cloudy
- Precip. probability: 9%
- Precipitation: 0"
- Wind: 8mphS 187°
- Humidity: 62%
- UV index: 5
- Sunrise: 7:03 am PDT
- Sunset: 6:08 pm PDT
- details ▼
- Saturday
- Oct 24, 2026
- 77°F
- 61°F
Mostly Sunny
- Precip. probability: 4%
- Precipitation: 0"
- Wind: 8mphWNW 293°
- Humidity: 55%
- UV index: 5
- Sunrise: 7:04 am PDT
- Sunset: 6:07 pm PDT
- details ▼
- Sunday
- Oct 25, 2026
- 77°F
- 63°F
Partly Cloudy
- Precip. probability: 6%
- Precipitation: 0"
- Wind: 9mphS 183°
- Humidity: 56%
- UV index: 5
- Sunrise: 7:04 am PDT
- Sunset: 6:06 pm PDT
- details ▼
- Monday
- Oct 26, 2026
- 75°F
- 61°F
Partly Cloudy
- Precip. probability: 13%
- Precipitation: 0"
- Wind: 9mphS 190°
- Humidity: 57%
- UV index: 5
- Sunrise: 7:05 am PDT
- Sunset: 6:05 pm PDT
- details ▼
Mixed conditions are forecasted for the coming ten days, and a mix of cloud-filled, dry and sunny, damp and turbulent weather is anticipated.
Rain is expected on Wednesday and Thursday.
Substantial differences in temperature are forecasted across the forecast period. Maximum temperatures are forecasted between 68°F and 82.4°F, while nighttime temperatures are expected to vary from 60.8°F to 68°F.
Sunday will be the warmest day, with a maximum temperature of 82.4°F; with the highest temperature of 68°F, Thursday will be the coldest day.
Rain is expected on Wednesday and Thursday.
Substantial differences in temperature are forecasted across the forecast period. Maximum temperatures are forecasted between 68°F and 82.4°F, while nighttime temperatures are expected to vary from 60.8°F to 68°F.
Sunday will be the warmest day, with a maximum temperature of 82.4°F; with the highest temperature of 68°F, Thursday will be the coldest day.
Updated: Oct 18, 2026 @ 06:17:20 UTC
Published by: Weather U.S. | About Us
Data Sources | weather.com | Weather
Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | weather.com | Weather
Weather Forecasting & Climate
Frequently asked questions
Tomorrow, sunshine will likely continue with scattered clouds at most.
Tomorrow, the highest temperature will be 82.4°F, while the lowest temperature will be 64.4°F. The maximum heat index, which reflects the perceived temperature due to humidity levels, is computed to be 82.4°F.
The highest temperature will be uncommonly higher than the average maximum of 73°F in October. Tomorrow, the lowest temperature will be in line with the average low temperature.
The highest temperature will be uncommonly higher than the average maximum of 73°F in October. Tomorrow, the lowest temperature will be in line with the average low temperature.
On Sunday, in Costa Mesa, sunrise will be at 6:59 am and sunset at 6:14 pm (PDT).
Tomorrow, the daylight will last for 11h and 16min.
