More transported smoke from the west October 12-13, 2017

If you've been following the news, you'll have likely heard about the terrible wildfires raging in California. Many people have died, homes and businesses have been destroyed, and some of the worst air quality on record has been measured. The strong dry winds are not helping the situation, and many people have been evacuated as the fires continue to spread. This has been a long fire season. I was getting ready to write a summary of the season (which I will post soon), but we are getting more smoke now in Fort Collins.

I noticed the smoke as I was leaving work last night (October 12^th*), and I snapped this picture (getting use to my solar field pictures yet?). It looked hazy again today (October 13^th).

Looking north northwest from the CSU Atmospheric Science building at 5:08 PM MT on 12 October 2017.

CDPHE had this Colorado Smoke Outlook today (October 13^th):

COLORADO SMOKE OUTLOOK: Friday, October 13, 2017, 8:05 AM MDT Wildfire smoke is being transported into Colorado from fires burning in the western United States. Impacts from this smoke are most likely along the Northern Colorado Front range and for locations east of the Continental Divide, however hazy and smoky skies may be noticed throughout the state. No significant impacts on public health are expected.

Where is this smoke from?
Trying to determine the source of the smoke, I turned to the satellite images. The source hasn't been as clear to me because the plumes are not as distinct. The MODIS-Terra images did look like there was some smoke over Wyoming and Utah earlier in the day yesterday.

MODIS-Terra True Color Image from October 12^th, 2017. Retrieved from https://worldview.earthdata.nasa.gov/. The line is from the two different overpasses being put together. 

The HMS smoke product seems to agree, showing plumes stretching over Utah, Wyoming, and NW Colorado both on October 12^th and October 13^th that could have hit us in Fort Collins as well. There was also a prescribed fire near Denver, a wildfire in Utah, and some prescribed fires in SE Idaho. Some of the smoke forecast models (Bluesky and HRRR) seemed to suggest that some of the smoke in Colorado could be from those sources as well. However, these do not show up in the satellite images, so I would wager a guess that this smoke is mostly from fires in California.

HMS smoke and fire product for 12 October 2017. Data from satepsanone.nesdis.noaa.gov.

What was the impact on our surface air quality?

You can notice the higher concentrations in the measured PM_2.5 in Fort Collins. The increase started right around the time that I was leaving work on Thursday, October 12^th.

PM_2.5 measured in Fort Collins, CO for October 10-13, 2017. Data from https://www.colorado.gov/airquality/.

*Originally posted October 13^th, updated October 17^th, 2017.