Last Updated on July 8, 2025 by The HD Post Staff

INLAND EMPIRE – The National Weather Service (NWS) has issued a heat advisory for the Inland Empire, including the valleys of San Bernardino and Riverside counties.

High temperatures of 95 to 104 are expected from 10 a.m. Wednesday to 8 p.m. Thursday.

NWS said hot temperatures may cause heat illnesses.

“Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors,” said the NWS advisory.

Air quality alert

NWS also issued an air quality alert for harmful levels of ozone (smog) air pollution for inland Orange County, the Santa Ana Mountains, the Inland Empire, the San Bernardino Mountains, the Riverside County mountains and the Coachella Valley.

The alert began Monday at 2:30 p.m. and will remain in effect until Thursday at 8:00 p.m. 

NWS said the highest ozone levels typically occur during the afternoon and early evening hours.

“Ozone air pollution can cause serious health problems, including trouble breathing, asthma attacks, and lung damage,” according to NWS.

It adds that 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.

Tips to keep indoor air clean

NWS says 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