Morning sun obscured by heavy smoke at the climate observatory on the University of Minnesota's St. Paul campus on July 16, 2026.
Image courtesy of Minnesota State Climatology Office
**Ongoing story as of July 16, 2026**
Minnesota made it through the first half of summer 2026 with few wildfire smoke issues, but that all changed after fires erupted in and near the Boundary Waters in early and mid-July, producing the most intense smoke pollution on record in the state.
The fires began in the northern forests on July 7th, with activity increasing and expanding rapidly in the following days as hot conditions spread throughout the region. By July 16, over 50 thousand acres had been burned, with little if any containment of the fires.
The growing fires released increasingly dense smoke, prompting the Minnesota Pollution Control to issue Air Quality Alerts, first in concentrated areas of northern and northeastern Minnesota, but eventually covering the vast majority of the state. On Wednesday July 15th, the densest plume pushed southward, through the Arrowhead, and into east-central, central, and eventually parts of southern Minnesota, prompting the MPCA to heighten many alerts to the "Maroon" or "Hazardous" level, which is the most dangerous category on the Air Quality Index (AQI). In many areas including the Twin Cities, this level of alert had not been issued previously.
At a West Duluth sensor, the concentrations of fine particulates apparently broke the state's all-time hourly record, measuring 617.8 ug/m3 ("micrograms per cubic meter of air") at 10 AM. That record may have been eclipsed later at Ely, and throughout Wednesday and Thursday, pollution concentrations across much of the state were at levels scarcely if ever measured previously. A sensor at Blaine recorded 342.8 ug/m3, setting a new record for the Twin Cities area by a large margin. The MPCA will need time and lab analysis to confirm any new records, but provisionally, this is the worst and most widespread smoke outbreak on record for the state.
Most air quality sensors have only been deployed over the past 1-3 decades, so historical comparisons are not easy to make. However, dense smoke often reduces visibility to two miles or less, and the presence of smoke is a noted entry in standard hourly weather observations. In 2025, the State Climatology Office examined records of smoke observations back to 1976 and found no years with comparable smoke frequency and intensity to the smoky summer of 2025. Along similar lines, the 2026 event appears to be substantially worse than any other smoke outbreak in Minnesota in at least 50 years.
Posted July 16, 2026
KAB