Dense fog and inversion settle into Salt Lake Valley

Stubborn, dense fog clouded the Salt Lake Valley on Tuesday afternoon, bringing with it reduced visibility, slick roads and worsening air quality.

The fog materialized in the valley bottoms near the Great Salt Lake and Utah Lake on Tuesday morning and didn’t dissipate as temperatures rose throughout the day, according to the National Weather Service. As the fog clings to particulate matter in the air from the ongoing inversion, it will stick around overnight and likely will lower visibility during Wednesday morning commutes.

Forecasters put the western two-thirds of the state under a hazardous weather outlook through Wednesday because of the fog.

The outlook warned of “very poor visibility” and slick roads.

Along with the fog, the amount of particulate matter in the air — which determines the air quality index — has been rising steadily in Salt Lake City since Monday, according to the Utah Department of Environmental Quality.

Officials said air quality levels were in the “moderate” range Tuesday. Pollution levels will worsen into Wednesday and Thursday, raising the index from “moderate” to “unhealthy for sensitive groups.”

When air quality is deemed unhealthy for sensitive groups, people with lung diseases, children and older adults, and people who are active outdoors should reduce their time spent outside, according to the department.