Yosemite’s spring is speeding up
Yosemite’s waterfalls are peaking earlier than usual because March was unusually warm and dry, and the Sierra Nevada snowpack measured on April 1 was near record lows — so the classic spring window is arriving and fading faster than normal. (That early melt, combined with an unusually hot, snowless winter, is also raising spring wildfire risk across wide parts of the U.S., according to recent reporting.) (uniondemocrat.com) (insurancejournal.com)
Yosemite’s big waterfall season usually builds through spring, but park staff said the runoff had already started “about a full month or so earlier than most years” by March 11 after a warm, dry stretch in the central Sierra Nevada. (nps.gov) That shift showed up in the state’s most important snow measurement on April 1, when California officials went to Phillips Station and found no measurable snow at all. The California Department of Water Resources said record-hot March temperatures and rain at elevations that normally hold snow erased the snowpack months ahead of schedule. (water.ca.gov) Snowpack is the mountain’s savings account: winter stores water as snow, and spring cashes it out into rivers and waterfalls. When the account is small, the waterfalls can roar early and then drop faster because there is less cold snow left to melt in May and June. (nps.gov) Yosemite’s own April 1 numbers were stark. The park said snowpack in the Tuolumne River basin was 22 percent of average and in the Merced River basin it was 27 percent of average, even as Yosemite Falls, Vernal Fall, Nevada Fall, and Bridalveil Fall were all flowing high this week. (nps.gov) That is why visitors can get fooled by what they see in April. A waterfall can look huge now because the melt arrived early, while the season as a whole is still short because the Sierra Nevada entered April with one of its weakest snow years on record. (water.ca.gov) The state’s broader survey shows how little reserve is left outside Yosemite too. Preliminary April 1 data put the statewide snowpack at 18 percent of average, and officials said this year is likely the second-lowest April snowpack on record. (water.ca.gov) Yosemite has been warning for years that warming winters change the park’s timing, not just its totals. The National Park Service says long snow records in and near Yosemite show declines in the heaviest snowpack years at low elevations, which shortens winter travel and brings earlier stream crossings and runoff. (nps.gov) The same early melt that reshapes waterfall season also dries out fuels sooner. The National Interagency Fire Center’s April outlook said fire activity increased across the United States in March, and its maps show above-normal significant fire potential spreading across parts of the Southwest and southern Plains in April before expanding more broadly in late spring and early summer. (nifc.gov) So Yosemite’s spring is not disappearing so much as getting compressed. The park still has high water right now, but the classic window when snowmelt builds, peaks, and lingers is arriving earlier than visitors expect and is more likely to fade before summer does. (nps.gov)
