Every February Yosemite waterfall turns to lava

YOSEMITE NATIONAL PARK, Calif. (AP) — A window of time just opened in Yosemite National Park when nature photographers wait, as if for an eclipse, until the moment when the sun and earth align to create a fleeting phenomenon.

Every February Yosemite waterfall turns to lava

This marvel of celestial configuration happens in a flash at sunset in mid-February — if the winter weather cooperates. On those days the setting sun illuminates one of the park’s lesser-known waterfalls so precisely that it resembles molten lava as it flows over the sheer granite face of the imposing El Capitan.

“Horsetail is so uniquely situated that I don’t know of any other waterfall on earth that gets that kind of light,” said Michael Frye, who wrote the book “The Photographer’s Guide to Yosemite.”

“How many are perched on a high open cliff? Most are in an alcove or canyon and won’t get the sun setting behind it. Yosemite’s special geography makes this fall distinctive,” he said.

But photographing Horsetail is a lesson in astronomy, physics and geometry as hopefuls consider the azimuth degrees and minutes of the earth’s orbit relative to the sun to determine the optimal day to experience it. They are looking for the lowest angle of light that will paint Horsetail the colors of an iridescent sunset as rays reflect off granite behind the water. It materializes in varying degrees of intensity for the same two weeks every year.

“If you hit it at just the right time, it turns this amazing color of gold or red-orange,” said Frye, a photo instructor with the Ansel Adams Gallery in the park.

HERE When conditions come together, the scrawny Horsetail Fall is the shining star of a park famed for its other waterfalls — raging Yosemite Fall and Bridalveil Fall. But Horsetail is the longest free-falling one, with a drop of 1,500 feet before it hits granite and spills another 500.

The fire lights up around dusk and lasts for about two minutes. The best views are east of El Capitan along the main roads into and out of Yosemite Valley. Most photographers gather at the El Capitan picnic area, a small pullout marked only by a sign with a table etched on it. But park officials say the inexperienced can look for the hordes of tripods and cameras to find a vantage point.

Recent storms and snowfall mean the finicky fall is flowing again, and park officials are hopeful it will last through February 24, which is generally the last day of the year it can be seen. Once an obscure event, park officials say that Internet discussions have made it more popular in recent years.