Bethany Gediman

Every mid-February, the setting sun backlights Horsetail Fall in Yosemite National Park.

Lava hasn’t flowed in Yosemite National Park for millions of years, but for the next few weeks, visitors can get a glimpse of a natural phenomenon that echoes the area’s fiery past.

Instead of molten rock, however, what the locals call a “natural firefall” owes its existence to a fortuitous convergence of water, sunlight and season.

“There's a little waterfall on the east end of El Capitan called Horsetail Fall that catches the light for just a few fleeting moments,” said filmmaker Steven Bumgardner. “It creates the illusion of a waterfall of fire, not unlike lava.”

The firefall only occurs for approximately two weeks in mid-February when the setting sun shines up the Yosemite Valley, effectively backlighting the ribbon-like cascade.

“Some years, it’s bright red; some years, it’s more golden,” said Park Ranger Kari Cobb. “As long as the weather’s clear and there’s enough water, it’ll light up.”

This year, viewing looks promising thanks to recent snowfall that’s now melting and feeding the seasonal stream that flows into Horsetail.

“It’s flowing right now,” said Cobb, “but it probably won’t last for two weeks unless we get another storm.”

While the firefall may resemble lava, it actually takes its name from a more recent page of Yosemite history. From the 1930s to 1968, visitors to the park were treated to the sight of the original Yosemite Firefall, a nightly event in which park employees pushed a pile of burning embers over the edge of Glacier Point, creating the impression of a glowing cascade of water.

“Eventually, they came to realize that pushing embers over a cliff in Yosemite probably wasn’t the best thing to do,” said Cobb.

There are, of course, no such concerns with the current version of the firefall, although visitors should realize that its appearance is dependent on natural variables that vary from year to year, day to day and even minute to minute.

“The whole experience is about an hour although the peak is only a fraction of that,” said Bumgardner, who produced a video of the firefall for the Park Service during last year’s flow.

“You just never know if that peak is going to be right now or in another five minutes,” he said. “When in doubt, take a picture, wait a little longer and take another.”

Rob Lovitt is a longtime travel writer who still believes the journey is as important as the destination. Follow him at Twitter.

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