Air quality in Lake Tahoe ranks worst in North America right now

The air quality in the Lake Tahoe Area on Tuesday morning was considered the worst in all of North America.

Air quality experts say the smoke from the Caldor Fire in El Dorado county has created dangerous, toxic air.

This week, readings on AirNow showed a 620 AQI in Tahoe City. The Air Quality Index goes up to 500. Anything above 500 is labeled as "beyond index."

But those same tests show the air quality in Tahoe has been changing almost daily during the past month, due largely to the winds. And there are still blue skies, and clear air, on many days around the lake.

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This story was reported in Oakland, Calif.