Intense forest fires in western North America during August, 2017, caused smoke plumes that reached the stratosphere. While this phenomenon has often been observed, this particular event caused increases in stratospheric aerosol extinction at higher altitudes with greater magnitude than previously observed in the satellite record. Here we use multiple satellite limb sounding observations, which provide high sensitivity to thin aerosol layers and good vertical resolution, to show that enhancements in aerosol extinction from the fires reached as high as 23 km in altitude and persisted for more than 5 months. Within one month, the aerosol is observed to cover latitudes from 20°N to 60°N, which is essentially the northernmost limit of the observations. At mid‐latitudes between 15‐20 km altitude, the sustained level of median aerosol extinction measured at 750 nm increased by almost an order of magnitude, from approximately 10-4 km−1 to nearly 10-3 km−1. •Agreement between limb scatter and occultation measurements is generally within 20% despite potential bias due to modified aerosol shape and composition.