At this point, with the National Park Service beginning plowing only yesterday, there is no way anyone can know what the opening date will be this spring. But we are getting lots of calls and emails, so we figured it was worth posting what we do know.

The average opening date is at the end of May, and this April’s snowpack water content is slightly above average at 112% at Tioga Pass, 96% in Dana Meadows, 102% in Tuolumne Meadows, 92% at Tenaya Lake, and 134% at Gin Flat. Plowing typically begins April 16th, and weather and plowing conditions can significantly speed or slow their progress. Based only on snowpack I would expect an opening date in early June, however a late May date is also probable. It will probably be closed in early May and open in late June, with the in-between dates questionable. Last year it opened on May 19th when April 1st Tioga Pass snowpack was 100% of average. The following table shows Tioga Pass April 1st snowpack and the opening date for years with similar snowpack since 1950. The only year with a denser snowpack than this year’s 46% was 1932 with 47%. Precipitation is for the Mono Inn, and for Lee Vining since 1989.

YEAR
SNOW WATER CONTENT
SNOW DEPTH
OPENING DATE
APRIL PRECIP
1950
22.2″
64.6″
May 30th
1954
24.2″
67.8″
May 26th
.06″
1956
38.0″ (density 45%)
85.0″
June 16th
1.57″
1958
30.7″
86.5″
June 22nd
1.64″
1962
30.8″
83.3″
May 26th
0.11″
1963
23.9″
62.0″
May 30th
1.34″
1970
28.0″
69.4″
May 15th
0.12″
1972
21.5″ (density 45%)
47.7″
April 11th
0.99″
1978
45.8″ (density  44%)
103.7″
June 3rd
0.73″
1981
22.2″
63.1″
May 15th
0.27″
1984
36.9″ (density 46%)
80.7″
May 19th
0.42″
1989
22.2″
62.2″
May 12th
1991
20.2″
65.9″
May 26th
Trace
1997
38.0″ (density 44%)
86.6″
June 13th
Trace
1999
31.0″
77.9″
May 28th
2000
26.2″
65.1″
May 18th
0.25
2002
31.1″
83.1″
May 24th
0.40″
2003
23.2″
61.1″
May 31st
1.18″
2004
26.1″ (density 45%)
57.6″
May 14th
Trace
2009
26.8″
67.9″
May 19th
0.30″
2010
30.1″ (density 46%)
65.7″
1.21″
so far

Tioga pass will often open late in a week with some notice from the park early in the week, and sometimes we hear rumors the preceding week. Otherwise no advance notice is usually given (aside from regular plowing updates that might hint at their progress) and you’ll need to check the road conditions each week and possibly even each day if you are planning a trip that week.

Usually the road opens from the east to the park entrance at the top in late April. This would allow walking/bicycling access into the park at that point, especially on weekends when the public has less of a chance of interfering with plowing operations (There have been conflicts in the past and the park may announce a policy on this–please stay out of the way of the road crews and obey all signs!).

Hwy 108, Sonora Pass, usually opens before Tioga Pass, and while this does add a couple of hours to the trip to Yosemite Valley (the trip to San Francisco is about the same), this could be a good backup alternative if you wish to plan your Memorial Day Weekend trip soon.

One comment

  1. So far NPS hasn’t even confirmed that plowing has started on Tioga Road. Sure would be nice if they said a little something.