February Light and the Fall That Glows

For roughly two weeks every February, when the conditions align, the light does something unusual here.

Horsetail Fall runs along the eastern shoulder of El Capitan from December through early spring, fed by snowmelt from the granite above. In the last hour before sunset, on days in mid-to-late February when the sky to the west is clear and the fall is running well, the setting sun hits the water at an angle that makes it glow. Not shimmer. Not reflect. Glow, in deep orange and red, the color of fire, pouring down a three-thousand-foot granite wall.

The effect requires specific conditions: the sun at the correct azimuth for the season, enough water in the fall to be visible from the valley floor, and no cloud cover blocking the western sky. It fails more often than it works. When it works, it is among the stranger visual events that occur in this valley without any human assistance.

Ansel Adams photographed a version of this effect, though the date of his photograph is not in the sources this recording uses.

For comparison: from eighteen seventy-two to nineteen sixty-eight, a commercial spectacle called the Yosemite Firefall ran every summer evening from Glacier Point, where burning embers were pushed off the cliff to cascade nine hundred feet in a stream of fire for waiting crowds below. The NPS ended it in nineteen sixty-eight as incompatible with natural park management. The natural light show on Horsetail Fall now draws larger crowds than the manufactured firefall ever did. The NPS issues crowd management advisories for it.

The Ahwahneechee managed fire throughout this valley for centuries, using controlled burns to maintain the meadows and drive game. The fall's February light has no connection to those practices. The coincidence is notable and the NPS does not currently connect them in its interpretive materials.