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Monday's wildfire smoke health advisory for the northeastern part of the state, issued by Colorado Department of Public Health and Environment, was allowed to expire at 9 a.m.
Haze and smoke from Pacific Northwest wildfires are to blame for the dirty haze hanging around the state's skies. And even though the formal health warning is over, the smoke in the air is still visible. The department recommends limiting outdoor activity when moderate to heavy smoke is present, especially for vulnerable groups.