Hundreds of flights have been cancelled or delayed at Denver International Airport due to bad weather around the country, as well as haze and smoke from wildfires in the West.

The delays were created "by the planes having to be spaced out due to visibility," said Alex Renteria, a spokesperson for Denver International Airport.

According to FlightAware, there were 329 delayed flights within, into, or out of the United States at Denver International Airport, with eight cancellations.

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Hundreds of flights were originally delayed due to the wildfires, but Denver airport spokesperson Alex Renteria subsequently acknowledged it was difficult to determine the exact number. Weather around the country, he added, also played a role.

The Federal Aviation Administration (FAA) implemented a temporary traffic control scheme for planes arriving at the congested Colorado airport on Monday.

According to the National Interagency Fire Center, there are presently 80 major wildfires blazing in 13 states throughout the US, scorching more than 1.1 million acres, primarily in western regions (NIFC). Montana has the most major wildfires, with 18, and Idaho is close behind with 17, according to the NIFC. The 80 major wildfires presently burning throughout the United States have almost 20,000 wildland firefighters and staff assigned to them.

After Oregon; California, Idaho, and Alaska are the states with the greatest acres burnt.

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According to statistics from InciWeb, the US clearinghouse for wildfire information, Oregon's Bootleg fire, which has been blazing in the Fremont-Winema National Forest near the Oregon-California border since July 6, has burnt 303,791 acres with a 25 percent containment.

Fire spokesperson Katy O'Hara told CNN that weather circumstances ought to give in order for the fire to be quelled.

"We are experiencing extremely dry conditions with record to near record temperatures. Conditions on the ground due in part to the historic drought have accelerated the fire season. The combination of the weather and fuel conditions have led to rapid growth of the fire," O'Hara said.

According to CAL Fire, 5,267 wildfires have burnt more than 200,000 acres of property in California as of July 18. This is more than five times higher than last year's record-breaking season, when 4,336 fires destroyed 39,041 acres of land in the state.

Last year, more than 4.2 million acres were burnt, indicating that these figures might significantly alter later in the year, with the majority of California's usual fire activity occurring in the summer and fall.

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According to airport director Brian Sprenger, the wildfires have had a knock-on impact on transportation, with fuel supply difficulties prompting aircraft cancellations at Bozeman Yellowstone International Airport in Montana.

"Each airline provides their own fuel through their providers but today, some have had their fuel delivery delayed due to increased fire suppression needs throughout the West that has diminished supply in Montana in an already tight fuel environment," Sprenger said in an email to CNN Sunday.