The National Weather Service yesterday declared the area's air to be stagnant, but the Metropolitan Washington Council of Governments said its quality, while poor, fell far short of being hazardous.
The federal weather watchers issued the season's first air stagnation advisory at noon yesterday after finding that a large high-pressure system had stalled over the Atlantic [WORD ILLEGIBLE] . They saud winds were too hight as budge the state air from the Washington-Maryland-virginia area where the advisory applies.
Dennis Bates, chief air-pollutions trackers for the Council of Governments, acknowledged the local atmosphere yesterday was a bit "murky". But official monitoring stations produced at 3 p.m. air quality index of only 68.
In COG's lexicon, that reading represented "poor" air. Generally, the agency issues an air-pollution alert only when its index breaks 100 at two stations, which indicates the air is dirty enough to be hazardous to the elderly and those with heart or respiratory problems.
Clouds, a natural haze that contributed to the air's murky appearance, and only moderately warm temperatures helped keep COG's index yesterday from soaring higher than it did. The mercury hit a high of 82 degree at 1:15 p.m.
Pollution levels tend to income hazardous locally when hot, direct sunlight oxidizes hydrocarbons from auto exhausts that become trapped in stagnant air. That explains why Washingtons tend to find themselves breathing the worst air during the summer.
And summer is months away.