Delta Airlines is once again slashing service at Memphis International Airport, eliminating flights from Memphis to Denver and Austin, Texas, in September.

The airline, which formerly operated a fortress hub at Memphis International, will also temporarily suspend service to Las Vegas this winter.

Delta did not disclose the reasons for the latest reductions to Memphis and Shelby County Airport Authority executives, but lack of demand, competition from other carriers and seasonal adjustments could have played a role, said Scott Brockman, president and CEO of the Airport Authority.

“Air service is a recipe that takes a lot of ingredients,” said Brockman. “They don’t offer us a detailed explanation as to why.”

Delta will be adding two Memphis flights to the airline’s global hub in Atlanta.

“Clearly, they’re trying to push more people through Atlanta,” said Brockman.

While Delta is eliminating some flights, the number of available seats on Delta flights will actually increase, because the airline will be adding larger flights to its fleet.

Delta’s number of nonstop destinations will go from 20 to 17 in November, and the airport’s number of nonstop destinations will go from 26 to 24. Denver is still served by both United Airlines and Frontier Airlines.

The flight changes are a result of Memphis International transitioning from a hub airport dominated by connecting flights to one focused on generating more origin and destination traffic.

“As an origin-and-destination market that is reinventing its air service, these are the challenges we now embrace,” said Brockman.

Frontier, which began service to Denver in March, is adding service to Washington Dulles in September. Southwest Airlines and United Airlines are each adding a flight to Houston in November. The overall