Today | Weather | Thursday, July 23, 2026
Active Weather Warnings

Weather in Mission Viejo, California

04:43 AM
Now
Cloudy Night
66° F
Feels Like 66°
Precipitation 0 %
Wind 4 mph
Humidity 89 %
Today
Cloudy Weather
Day 90°
Night 70°
Precipitation 0 %
Wind 7 mph
UV Index (0 - 11+) 11

Warning: Extreme UV Index Today: 11

Overexposure to the sun's harmful UV rays can cause sunburn and increase the risk of developing skin cancer, including melanoma. Protect yourself by wearing clothing that covers your skin, sunglasses, and a hat. Apply a broad-spectrum sunscreen with an SPF of 30 or higher every two hours, even on cloudy days. Minimize direct sun exposure during peak hours (10 AM to 4 PM) to reduce the risk.

Mission Viejo Weather Forecast Updated

21 minutes ago
Last updated on

Air Quality in Mission Viejo

NOW
32 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 6.04 µg/m³
PM10 23.48 µg/m³
O3 0.035 ppm
NO2 0.3 ppb
SO2 0.3 ppb
CO 0.07 ppm
NH3 0 µg/m³
NO 0 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.56.04 µg/m³
PM1023.48 µg/m³
O368.1 µg/m³
NO20.49 µg/m³
SO20.89 µg/m³
CO83.98 µg/m³
NH30 µg/m³
NO0 µg/m³

Weather Alerts and Warnings for Mission Viejo

Moderate Expected Likely

Heat Advisory

Heat Advisory issued July 22 at 9:01PM PDT until July 27 at 8:00PM PDT by NWS San Diego CA
Jul 22, 9:01 PM Jul 27, 8:00 PM
WHAT: High temperatures in the 90s and low temperatures in the
upper 60s and lower 70s expected.

WHERE: Orange County Inland Areas.

WHEN: Until 8 PM PDT Monday.

IMPACTS: Hot temperatures may cause heat illnesses.
+ Read More
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.
Updated: Jul 23, 4:21 AM Source: NWS Alert

Air Quality Alert

Air Quality Alert issued July 22 at 5:41PM PDT by NWS San Diego CA
Jul 22, 5:41 PM Jul 23, 5:45 PM
WHAT: The South Coast AQMD has issued an air quality alert due to
harmful levels of ozone pollution.
Visit https://www.aqmd.gov/alertinfo to check current and forecasted
air quality levels.

WHERE: in the South Coast Air Basin and Coachella Valley. Levels
of ozone pollution can vary by time and location depending on
emissions and air pollution transport.

WHEN: until 8 PM Monday. The highest ozone levels typically occur
in the afternoon and early-evening hours.

IMPACTS: Ozone air pollution can cause serious health problems,
including trouble breathing, asthma attacks, and lung damage.
Everyone can be affected, but sensitive groups such as people with
lung disease, older adults, people who are pregnant, children, and
those who spend a lot of time outdoors are at greater risk.
+ Read More
To protect your health, check air quality levels and act as needed: * When Air Quality Index (AQI) levels are "Unhealthy for Sensitive Groups" (orange), sensitive groups as specified above should limit extended or intense outdoor activity. * When AQI is "Unhealthy" (red), everyone may experience health impacts. Sensitive groups should avoid extended time outdoors. * When AQI is "Very Unhealthy" (purple), sensitive groups should avoid all outdoor physical activity. Everyone else should avoid extended or intense outdoor activity. * When AQI is "Hazardous" (maroon), everyone should avoid all outdoor physical activity. * ADDITIONAL DETAILS... To help keep indoor air clean when air quality is poor: * Keep windows and doors closed * Run your air conditioner and/or an air purifier * Do not use whole house fans or swamp coolers that bring in outside air if you have other methods to stay cool * Avoid other sources of pollution such as fireplaces, candles, incense, and grilling To help minimize outdoor ozone air pollution levels: * Limit the use of gasoline powered lawn and garden equipment until evening hours * Try to delay trips to the gas station and the use of household chemicals until the evening
Updated: Jul 23, 4:21 AM Source: NWS Alert