State officials are warning that levels of ozone, a gas formed when chemical emissions from power plants, factories and cars are exposed to sunlight, are forecasted to reach levels unhealthy for children, the elderly and people with asthma Monday.

The high ozone levels increased the likelihood of respiratory symptoms and breathing discomfort, especially among those groups, said officials from the state Department of Energy and Environmental Protection.

Connecticut residents should limit activity outside today, especially when ozone levels are predicted peak between 2 p.m. and 8 p.m. Monday.

"This weather can also impact healthy adults working or exercising outdoors," DEEP Commissioner Rob Klee said in a news release. "To minimize health impacts while working outdoors avoid prolonged strenuous activity and best if you exercise before noon or after 8 p.m."

Sunshine, a steady west-southwest wind and temperatures above 90 degrees Monday are contributing to poor air quality, allowing other emissions to mix into the ozone. Cold air moving across the state late Monday night will lower the ozone levels for Tuesday, according to the release.

People should wait to refuel gasoline-fueled vehicles and mowing lawns until after dusk, avoid unnecessary idling and refrain from recreational wood burning.

DEEP officials also recommended that residents help address air pollution by driving less, saving energy by setting air conditioners to 78 degrees and waiting until 8 p.m. to use energy-intensive appliances.