The National Weather Service has let us know that the smoke in Boulder County is primarily drifting into Colorado from the Pipeline Fire near Flagstaff, AZ, which ignited yesterday. Most of the smoke is currently elevated and not near the surface, except in the high country, but expect increased surface concentrations later today, as the hot conditions help mix down the air aloft.
Information from the Colorado Department of Public Health and Environment:
If smoke is thick or becomes thick in your neighborhood you may want to remain indoors. This is especially true for those with heart disease, respiratory illnesses, the very young, and the elderly. Consider limiting outdoor activity when moderate to heavy smoke is present. Consider relocating temporarily if smoke is present indoors and is making you ill. To temporarily relocate to an area with better air quality, consider using this map (https://fire.airnow.gov/) to identify the best area closest to you. IF VISIBILITY IS LESS THAN 5 MILES IN SMOKE IN YOUR NEIGHBORHOOD, SMOKE HAS REACHED LEVELS THAT ARE UNHEALTHY.