Smoke for July 23-24, 2017

If you were out and about in Fort Collins on Saturday (July 22^nd), you might have noticed a large smoke plume. I took this picture from the North College King Soopers parking lot.

Taken looking southeast from North College King Soopers parking lot at 12:33 PM on Saturday, July 23, 2017.

A few minutes later I took this picture looking south from where 287/14 and 287B/54G split. 

Taken looking south southeast from 54G at 12:42 PM on Saturday, July 23, 2017.

This was smoke from the Spring Glade grass fire near Coyote Ridge Natural Area. The fire started at approximately 11 AM (according to the Coloradoan, it may have been caused when a mower hit a rock and caused a spark). The heat and wind unfortunately made the situation worse, and the fire spread pretty rapidly.

The CDPHE put out the following advisory at 5:30 PM that evening: 

Air Quality Health Advisory for Wildfire Smoke

Issued for Larimer County 4 miles southwest of Fort Collins

Issued at 5:30 PM MDT, Sunday, July 22, 2017

Issued by the Colorado Department of Public Health and Environment

Affected Area:  Locations in east central Larimer County near Horsetooth Reservoir and the Coyote Ridge and Cathy Fromme Prarie Open Space areas including, but not limited to, the Stout and Rim Rock areas and other portions of southwestern Fort Collins, and portions of northwestern Loveland.

Advisory in Effect: 5:30 PM MDT, Saturday, July 22, 2017 to 9:00 AM MDT, Sunday, July 23, 2017.

Public Health Recommendations: 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.

Outlook:  Areas of moderate to heavy smoke will persist Saturday evening near Horsetooth Reservoir and the ridges and foothills adjacent to the fire. Light and variable winds are expected to be primarily out of the east or southeast late in the day on Saturday, however overnight, light drainage winds will allow smoke to reach lower terrain, below the fire. Depending on fire activity, moderate to perhaps heavy smoke is possible for neighborhoods in the immediate vicinity of this fire, while lesser concentrations and the smell of smoke will likely affect larger areas of south and southwestern Fort Collins and north and northwestern Loveland.

So, how did this affect our air quality in Fort Collins? 

Time Series of PM2.5 concentrations in Fort Collins (black) and Greeley (red) for 20 July - 25 July, 2017.

We did see that PM_2.5 concentrations built up over night (from the 22^nd into the 23^rd) both in Fort Collins and in Greeley. The peak concentration was 19 ug/m³ at the Fort Collins monitor at 11 PM on Saturday night. Concentrations stayed higher on Sunday, July 23^rd, but this could have also been from long range transport of smoke. Looking at the HMS for Sunday, there was smoke over northern Colorado from the fires in Montana and Idaho. The fires there are still burning, which is unfortunate for me as I'm travelling to Idaho and Montana this weekend.

HMS Smoke Product Plumes (http://satepsanone.nesdis.noaa.gov/FIRE/fire.html) for July 23, 2017 at 1845 GMT (12:45 PM MT, left) and 2130 GMT (3:30 PM MT).