SEATTLE – A smog watch is now in effect for King, Kitsap, Pierce and Snohomish counties.

The Puget Sound Clean Air Agency says hot air is moving into the Puget Sound region from the south, bringing a temperature inversion along with it that will trap air pollution and impact air quality over the next several days.

People with asthma and parents of children with asthma are advised to limit outdoor activities during hazy, sunny, hot weather when ozone levels are high. Adults with lung and cardiovascular diseases should also be mindful of poor air quality.

Expect "moderate" air quality in rural areas of King and Pierce counties on Tuesday, falling to "unhealthy for sensitive groups" Wednesday as ozone levels rise. In core urban areas, air quality is expected to fall to "moderate" on Wednesday.

Residents are asked to do the following to help alleviate the air problem.

- Drive your most fuel-efficient car and combine errands into one trip.

- Skip gasoline-powered yard work and gas-fueled recreation.

- Carpool or ride the bus to work, events and outings. 

- Gas up your car in the cooler evening hours.