CHEYENNE, Wyo. (AP) — Large areas of Yellowstone, Yosemite and Glacier national parks could remain closed to summer traffic weeks later than usual, while visitor centers and campgrounds at several other national parks might have to close.

That's the scenario a group of National Park Service retirees outlines under steep federal budget cuts set to take place starting March 1.

The Park Service isn't denying any of it. Park Service spokesman Jeffrey Olson said Wednesday that visitors to any of the 398 Park Service sites nationwide can indeed expect reduced hours and services if the cuts take effect.

The Coalition of National Park Service Retirees warns of specific closures at 11 national park sites. That includes delayed spring snow plowing in Yellowstone, Yosemite and Glacier.

Visitor centers could close in at least three parks.