Tioga Road in Yosemite National Park, one of America's most beautiful mountain highways, will open at noon Monday over 9,943-foot Tioga Pass.

In addition, Caltrans tentatively has planned to open Highway 108 over 9,628-foot Sonora Pass at noon Friday.

At the same time at Lassen Volcanic National Park, crews are dealing with a 130-inch snowpack at Lake Helen on the Lassen Park Highway/Highway 89, and based on past years, will not open the road until mid- to late May.

Tioga Road connects Crane Flat, 14 miles from the Big Oak Flat/Highway 120 park entrance, to Tuolumne Meadows and, a short distance beyond, Tioga Pass. It's about 48 miles from Crane Flat to the pass.

The annual opening provides access to the Yosemite Creek Trailhead (which leads to the brink of Yosemite Falls), Tenaya Lake, and trailheads for Lembert Dome, Mount Dana and access to the Pacific Crest Trail and John Muir Trail at Tuolumne Meadows.

Tioga Road opened at Crane Flat to bicycle traffic over the weekend, reported Yosemite's Kari Cobb at park headquarters. Park rangers are scheduled to drive the road Wednesday and assess conditions for public access, and open some facilities for spring. Last week, snowplow crews punched through to the Tioga Pass Entrance Station, with clear pavement on Highway 120 east through the Lee Vining Canyon to Highway 395 and Mono Lake.

With the onset of an early spring in the high country, Yosemite's wilderness winter rangers left their station for the year a week ago at 8,600-foot Tuolumne Meadows. Winter ranger Marea Ortiz said bare patches of asphalt on Tioga Road already were appearing before snowplow crews arrived last week.

The snowpack at Tuolumne Meadows was measured at 16 inches, 43 percent of normal. All high-mountain lakes are still frozen, of course.

"The sounds of spring are apparent through the area," Ortiz said. "Birds are now coming through and are very vocal on these spring mornings. The Tuolumne River is starting to open up and summer will be here soon."

Last year park officials were not able to clear the road until June 18.

Updates: For highway conditions at Yosemite, go to nps.gov/yose or phone (209) 372-0200. For Sonora Pass/Highway 108 and Ebbetts Pass/Highway 4, go to dot.ca.gov/hq/roadinfo/mtnhwys.htm or phone (800) 427-7623.