A dense smoke layer from dozens of raging wildfires darkened the skies and fouled the air along much of the West Coast Thursday and was expected to hover in the region at least through the weekend.

Eerie orange and red skies across California, Oregon and Washington had mainly turned gray.

Meteorologists say that’s thanks to stronger winds coming in from the Pacific Ocean that helped to disperse thick smoke filtering sunlight.

But as a layer of air blocking the smoke from reaching the ground started dissipating, smoke particles began mixing with ground-level air worsening air quality in California and Oregon.