Air Quality Awareness Week began Monday, with the day’s focus on ozone, which at ground level can cause health problems.

However, the ozone level in the Washington area was predicted to fall Monday well within the “good” range in the Air Quality Index forecast published by the Metropolitan Washington Council of Governments.

Although Wednesday starts “ozone season” in much of the country, Washington had at least one big thing going for it Monday. That was the blanket of gray clouds that covered the sky for much of the day.

Sunlight helps produce ground-level ozone, and ozone production is curbed by clouds, rain, breezes and cooler weather. That was at least a partial description of conditions Monday in the Washington area.

At Reagan National Airport, as of 5 p.m., the day’s average sky cover was rated a nine on a scale of 10.

It was wet, foggy and hazy. About a quarter inch of rain fell, and the temperature was nine degrees below the normal 71.