Afternoon highs in the mid-90s will feel even more uncomfortable today. Metro Atlanta's air quality at daybreak on Monday was already well into the zone considered unhealthy for sensitive people.

The mercury could climb a degree or two higher than Sunday's 94 reading, forecasters at the National Weather Service said.

Sunday was the hottest day so far this month, but the high fell several degrees short of the 98-degree reading on June 9. Average high for July 21 is 90, the Weather Service said.

Atlanta's air quality index was in the "orange" zone at sunrise Monday, according to the Georgia Environmental Protection Division. That means children and adults who play, exercise or work outside, and people with respiratory disease such as asthma should limit outdoor exertion.

Air quality can range from green, for good quality, through yellow, orange, red and purple to black, the worst quality of all.

The forecast for metro Atlanta calls for highs around 96 on Tuesday. There is a 20 percent chance of showers and thunderstorms on Tuesday, rising to 30 percent Tuesday night and 40 percent Wednesday, forecasters said.

Cooler air moving into the state on Wednesday should keep highs in the mid-80s, the Weather Service said.

Thursday will be mostly cloudy, with a 20 percent chance of showers and highs in the upper 80s.

Mostly sunny skies and highs in the low 90s are predicted for Friday and Saturday, followed by partly cloudy skies, a 20 percent percent chance of showers and highs near 90 on Sunday.

Staff writer Chris Reinolds contributed to this article.