The suspended ash from the forest fires in Arizona and New Mexico are resulting in red sunsets along the Front Range of Colorado. During the day, the sun shines through the ash which gives everything a yellowish color.
The major contributor to the ash is the Wallow fire near Alpine Arizona which has already burned over 200,000 acres -- over 300 square miles.
Note: Check out this link for Active Wild Fires. Rarely is this current, but may have been the situation a day or two ago.