Colorado issues air-quality alerts for all counties as wildfire smoke spreads

Colorado’s public health department issued air-quality alerts for nearly every county in the state on Tuesday as smoke from large wildfires across the West spread over the Rockies and into the Front Range. The haze was not primarily from fires burning inside Colorado, according to the National Weather Service and Colorado Public Radio. Forecasters said smoke was drifting in from Utah and from larger fire complexes in Washington, Oregon and Idaho. State officials said the advisory was in effect through 9 a.m. Wednesday, with improvement expected to be gradual rather than immediate. ### Where is the smoke over Colorado coming from? The National Weather Service said the haze over Colorado this week was being carried in from multiple large fires burning hundreds of miles away. Zach Hiris, a meteorologist with the National Weather Service in Boulder, told CPR News that “a variety of different sources of wildfire smoke” were feeding the plume over the state, including fires in central Utah and larger fire complexes in Washington, Oregon and Idaho. (cpr.org) Denver7 reported Monday that smoke from fires in Washington and Montana was blanketing parts of Colorado, and Chief Meteorologist Lisa Hidalgo said the haziest conditions were expected to last through early Wednesday. Hidalgo said a cold front was breaking down a ridge of high pressure that had previously kept more of the smoke farther north. (cpr.org) ### How broad were the alerts? Colorado Public Radio reported on August 4 that the Colorado Department of Public Health and Environment had issued air-quality alerts for nearly every county in the state, stretching from the Western Slope to the Eastern Plains, through 9 a.m. Wednesday. The department’s air-quality page says it issues alerts or advisories when conditions indicate Colorado might experience elevated air pollution levels. (denver7.com) The Colorado Sun reported that moderate to heavy smoke was expected in places including Rifle, Vail, Aspen, Breckenridge, Fairplay, Cañon City, Colorado Springs and Pueblo, with smoky conditions likely to last a few days. The Denver Post separately reported that the warning covered every Colorado county. ### What did officials say people should do? Scott Landes, supervisor of meteorology with the Colorado Department of Public Health and Environment, told CPR News that people should stay indoors if smoke becomes thick in their area. (cpr.org) Landes said the advice was especially important for older adults, young children and people with heart or respiratory conditions. He also said healthy people should consider reducing strenuous outdoor activity while smoke levels remain elevated. (coloradosun.com) CDPHE says fine particles known as PM2.5 are the biggest health concern in wildfire smoke. The department says smoke exposure can irritate the eyes, nose and throat, cause coughing and difficulty breathing, worsen asthma and other lung disease, and increase risks for heart-related complications. ### Why were conditions expected to improve only slowly? Hiris told CPR News that near-surface smoke — the smoke with the biggest effect on breathing and local air quality — was expected to begin diminishing on Wednesday. (cpr.org) He added that winds would continue carrying smoke into Colorado from the west and northwest over the next several days, which meant the haze might ease before it fully clears. (cdphe.colorado.gov) Lisa Hidalgo told Denver7 that smoke should start clearing toward the end of the week as the ridge of high pressure rebuilds. CPR also reported that Landes expected many counties would probably remain under some form of air alert even after Wednesday morning. ### Where can people check conditions next? CDPHE directs residents to its statewide air-quality advisories page for current conditions and forecasts and to the Colorado Smoke Blog for updates on wildfire activity, prescribed burning and smoke from out-of-state sources. (cpr.org) The department says it also offers email alerts for Colorado air quality. (cdphe.colorado.gov) (denver7.com)