Inclement weather has plagued areas of the U.S. in the first half of the weekend, with dangerous conditions including heavy snow, a major ice storm and unusual tornado activity.

A major ice storm has created treacherous driving conditions across Iowa and eastern Nebraska and prompted temporary closures of Interstate 80 after numerous cars and trucks slid off the road.

Despite the foreboding skies, there was little scent of smoke and the air quality index did not reach unhealthy levels. The sheer amount of smoke, the multiple layers of smoke above us in the atmosphere are combining to darken our sky, he said. Air quality warnings were issued throughout the Pacific Northwest, and people in communities from southern Oregon to north of Seattle have seen blood red skies and choking smoke. Gass said winds coming from the Pacific Ocean will likely continue to push the smoke across the West, worsening air quality. In Phoenix, the skies were finally blue on Wednesday after a cold front swept through the region, keeping the wildfire smoke west and southwest of Arizona.