In May, we intend driving to Yosemite Park from San Francisco and onward over the Tioga Pass down to Death Valley. From there we will head to Las Vegas and the Grand Canyon before returning up the Pacific coast. The Tioga Pass is the only pass in the Sierra Nevada, but is closed during winter. Is there any chance of it being open by May 18? It would be a long detour, either north or south. - Brett Pollock
Lonely Planet's Sarah Bennett and Lee Slater write:
The "Plan Your Visit" section of the US National Park Service website has information on road opening and closing dates. Predicting when the Tioga road will open is difficult as it depends on when snow-clearing can begin - usually around mid-April, and taking up to two months. Last year the Tioga road opened on May 7, but in the previous two years it didn't open until mid-June.
Travelling over the Tioga Pass and then south along the Eastern Sierra Scenic Byway (Highway 395) is the quickest route to Death Valley (402km, five hours). If the Tioga Road is still closed, however, the alternative route via Highways 41 and 99 is a rewarding detour and not that much longer. Heading straight to Death Valley will take about seven hours (644km), but if you can spare the time, a few days exploring the Sequoia and Kings Canyon national parks en route will be time well spent. There you will find Kings River canyon, the United States' deepest, and General Sherman, the world's biggest tree. These alone will justify the extra distance.
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