For third day in a row, Spokane’s smoky air measures in ‘unhealthy’ category

Air quality in Spokane on Wednesday remained in the “unhealthy” category for the third straight day.

Monday began the latest stretch of intense smoky skies. It was the first day in 2018 in which the 1-to-500 air quality index reached 150 – the unhealthy category – for a 24-hour period. The index measures particulate matter 2.5 microns or smaller.

The index measured 171 at 6:15 a.m. Wednesday.

Since measurements began in 1999, there were no 24-hour readings in the unhealthy category until 2015. Since then, they have occurred in three of the last four years. And in 2017, three days had air quality indexes above 200. That’s in the “very unhealthy category.”