Front Range Action Day for Multiple Pollutants September 17, 2020

The Colorado Department of Public Health and Environment has issued an ACTION DAY ALERT at 4PM on Wednesday, September 16, 2020 for the Front Range Urban Corridor from Douglas County north to Larimer and Weld counties, including the Denver-Boulder area, Fort Collins and Greeley.

Smoke transported from both in-state and out-of-state wildfires will result in fine particulate concentrations reaching the Unhealthy for Sensitive Groups to Unhealthy range on Thursday. Fine particulate concentrations in the Unhealthy category will be most likely for locations along the I-25 corridor from Denver northward to Ft. Collins, with fine particulate concentrations reaching the Unhealthy for Sensitive Groups category for the rest of the Front Range region. Additionally, ozone concentrations could reach the Unhealthy for Sensitive Groups category Thursday afternoon in parts of the Denver metro area. For health recommendations, please see the Front Range Air Quality Forecast below.

This Multiple Pollutants Action Day Alert will remain in effect until at least 4 p.m. Thursday, September 17, 2020.

For statewide conditions, forecasts and advisories, visit:
www.colorado.gov/airquality/colorado_summary.aspx

At 10AM (MST), Thursday, 9/17/2020 the highest AQI value was 153 for Particulate less than 2.5 micrometers which indicates Unhealthy air quality. Increased aggravation of heart or lung disease and premature mortality in people with cardiopulmonary disease and older adults; increased respiratory effects in general population. People with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion; everyone else should reduce prolonged or heavy exertion.

The Colorado Department of Public Health and Environment and the Regional Air Quality Council's Summer 2020 Ozone Action Day Alert Program has concluded. The winter High Pollution Advisory Program begins on November 1. Air Quality Action Days or advisories for ozone for other pollutants, however, will be issued as needed at any time during the year and reported on this web page.

The Air Pollution Control Division's Winter 2020/2021 High Pollution Advisory Program will begin November 1. Thank you for your interest in and support for efforts to improve air quality for the citizens of the Denver- metro area.

Front Range Air Quality Forecast & Colorado Smoke Outlook

FRONT RANGE AIR QUALITY FORECAST:
Thursday, September 17, 2020, 7:00 AM MDT

Ozone concentrations are expected to be in the Moderate to Unhealthy for Sensitive Groups range on Thursday. For health recommendations, please refer to Fine Particulate Matter below.

Fine Particulate Matter concentrations are expected to be in the Unhealthy for Sensitive Groups to Unhealthy range on Thursday. Unhealthy concentrations of fine particulate matter are most likely for locations along and near the I-25 corridor from Denver northward to Ft. Collins. In these areas, people with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion; everyone else, especially children, should reduce prolonged or heavy exertion on Thursday. For all other parts of the Front Range, people with heart or lung disease, older adults, and children, should reduce prolonged or heavy exertion on Thursday.

Carbon Monoxide concentrations are expected to be in the Good category on Thursday.

Nitrogen Dioxide concentrations are expected to be in the Good category on Thursday.

Visibility on is expected to be Poor to Extremely Poor on Thursday.

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For all other parts of Colorado not included in the above advisories, periods of smoke from both in-state and out-of-state wildfires will continue to move through the state at least into the upcoming weekend. Therefore, we suggest that unusually sensitive people reduce prolonged or heavy exertion in all areas not currently covered by one of the above advisories.

What if there is a wildfire or smoke in your area?
The focus of the Colorado Smoke Outlook is on large fires (e.g., greater than 100 acres in size). Nevertheless, smoke from smaller fires, prescribed fires, and/or smoke from new fires not yet known to CDPHE air quality meteorologists may cause locally heavy smoke. If there is smoke in your neighborhood, see the public health recommendations below.

Public health recommendations for areas affected by smoke:
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. IF VISIBILITY IS LESS THAN 5 MILES IN SMOKE IN YOUR NEIGHBORHOOD, SMOKE HAS REACHED LEVELS THAT ARE UNHEALTHY.

WHAT IS AN ACTION DAY?: An Action Day for fine particulate matter, carbon monoxide, ozone or other pollutants indicates that either current air quality is unhealthy or conditions are expected to worsen later in the day or on the next day. Action Days for air pollutants generally indicate that air quality will be in either the Unhealthy or Unhealthy-for-Sensitive-Groups categories according to the Air Quality Index. Action Days always convey overarching public health recommendations, and, according to season, trigger a variety of mandatory and voluntary pollution prevention measures. For example, during the summer open burning is prohibited when an Action Day for ozone and/or fine particulates is in effect. During the winter, residential burning restrictions are in effect when an Action Day for Visibility is in effect.

For a detailed description of both the AIR QUALITY INDEX and the VISIBILITY STANDARD INDEX please visit www.colorado.gov/airquality/brochure.aspx

COLORADO OPEN BURN FORECAST: For those with permits for open burning, that is the burning of waste materials or vegetation outside, check the following webpage to find out if open burning is allowed today. Keep in mind that open burning is prohibited when an Action Day is in effect:
www.colorado.gov/airquality/burn_forecast.aspx

FOR CURRENT FRONT RANGE ACTION DAYS/ADVISORIES:
www.colorado.gov/airquality/advisory.aspx

FOR CURRENT AIR QUALITY CONDITIONS STATEWIDE:
www.colorado.gov/airquality/air_quality.aspx

SOCIAL MEDIA:
www.facebook.com/cdphe.apcd
twitter.com/cdpheapcd

AIR QUALITY NOTIFICATIONS:
www.colorado.gov/airquality/request_alerts.aspx (CDPHE automated e-mail alerts)
www.enviroflash.info/signup.cfm (CDPHE forecasts via automated e-mails from the EPA)