High temperatures Monday prompted several schools to close early, and with just three days of classes left for Norwalk Public Schools, officials said they were playing it safe in buildings that aren't equipped with air conditioners.

Eleven schools had two-hour early dismissal: Nathan Hale, Ponus Ridge, Roton, West Rocks, Cranbury, Kendall, Naramake, Rowayton, Silvermine, Tracey and Wolfpit, all of which don't have air conditioning.

The Department of Energy and Environmental Protection also warned that ozone levels Monday would increase across Connecticut with temperatures in the 90s. Forecasts show temperatures in the same range Tuesday.

Experts say poor air quality will be unhealthy for infants, the elderly and people with respiratory or heart ailments.

The Red Cross advises people spending time outdoors to wear lightweight, light-colored, and loose-fitting clothing. They should also wear hats or use an umbrella, apply sunscreen often, and drink plenty of water before and during any outdoor activities. Officials also say people should avoid caffeinated or alcoholic beverages to minimize the chance of heat-related illness.

Officials are also warning drivers not to leave children or pets in parked cars.