There are more than 50 fires burning in the western United States, stretching from Montana to southern California. In total, more than 750,000 acres are burning.
Some very intense, active fires started in Washington state Monday.
9NEWS Meteorologist Marty Coniglio says that light northwesterly winds from the surface up to 20,000 feet in elevation provided a perfect path for the haze and smoke to push into Colorado.
Hazy conditions are expected Wednesday before a batch of cooler air and gusty winds moves in from the north early Thursday morning. This cold front will help thin out the smoke. Showers Thursday and Friday afternoon will also help scrub the air clean.
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