Parts of Washington, Oregon, California, Idaho, Nevada, Arizona and Utah are currently under critical and elevated risk of fire weather, according to the National Weather Service. Air quality in some regions has reached hazardous levels, and tens of thousands of firefighters are battling day and night to contain the thousands of fires, which are exacerbated due to .
Oregon Governor Kate Brown declared a wildfire emergency on Tuesday and ordered evacuations throughout the state. Most Californians remain under Red Flag Warning as the state surpassed its . Washington Governor Jay Inslee said this week that more acres burned on Labor Day "than in 12 of the last entire fire seasons in the state of Washington."
According to NASA, the color-changing skies are a result of smoke particles, which block certain wavelength colors from the sun.
"The smoke particles from the fires allow sunlight's longer wavelength colors like red and orange to get through while blocking the shorter wavelengths of yellow, blue and green," NASA said. "Those longer wavelengths give the sky a red or orange tinted appearance. Similarly, during sunrise and sunset times when the sun is near the horizon, sunlight has to travel through more of Earth's atmosphere to get to you. The additional atmosphere filters out the shorter wavelengths and allows the longer wavelengths to get through, providing reds and oranges during those times."
"What determines the color of the sky is the way your eye receives light which travels from the sun through the atmosphere," added CBS News Meteorologist and Climate Specialist Jeff Berardelli. "When all light easily passes through a clear atmosphere, then all the colors which make up the spectrum are detected by your eye as 'white light.' However, when light passes through a greater amount of atmosphere, especially at sunrise or sunset, it runs a greater chance of being scattered before reaching your eye."
"When smoke is thick it scatters so much light that the whole sky appears orange even during midday, the same as the horizon at sunset."