Wind has cast an apocalyptic-like haze over the Willamette Valley.
Smoke from the Whitewater Fire burning near Mount Jefferson and wildfires in British Columbia was pushed by offshore flow winds from the north and northeast.
Related: Oregon Governor Declares State Of Emergency Over Wildfires
The current air quality indexes for Hillsboro, Portland and Salem are unhealthy, according to the
Environmental Protection Agency
. Oregon Gov. Kate Brown
Wednesday as wildfire danger increased across the state.
The National Weather Service has issued an excessive heat warning until Friday night. The forecasted high in Portland Thursday is 106 degrees because of the smoke, instead of the originally anticipated high of 108 degrees.
"What the smoke is doing is that it's not allowing some of the solar radiation to actually come down to the surface. So that's keeping the highs mitigated ever so slightly," said David Bishop, a meteorologist with the National Weather Service in Portland.
A shift in the wind is expected Friday night and Saturday morning and should push the smoke out of the area.
Bishop said the excessive heat warning will be in effect until Friday night.
"We want people to keep an eye out for their fellow neighbors. We're also asking people to stay as hydrated as possible and to keep and eye on their four-legged friends," he said.