Tri-state residents are being warned to stay in cool places and avoid unnecessary outdoor exercise because heat is going to drive up ozone levels in much of the region.
Health and environmental officials say the combination of heat and smog is expected to push ozone levels above acceptable limits Friday in the New York metropolitan area, lower Hudson Valley and western New York.
Temperatures are expected to peak in the low 90s but with such stifling humidity it will feel closer to 100 degrees. An isolated thunderstorm is possible in the afternoon, forecasters say.
The air quality advisory is in effect from 11 a.m. to 11 p.m.
Children, people doing hard outside work and those with respiratory problems are at particular risk.
Saturday is expected to be a bit more bearable, with partly sunny skies and highs around 90 degrees with less humidity.
Strong storms are expected to hit the area Sunday afternoon before the weather improves next week, with highs in the mid-to-upper 80s and significantly better air quality forecast through Wednesday.
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