Time your visit right, and Horsetail Fall in Yosemite National Park glows like a strand of fire spilling over a shoulder of El Capitan. The ideal time see this short-lived annual spectacle? In 2011, a 10-day window of opportunity begins this weekend.

Photographer Michael Frye, who has spent more than 25 years photographing Yosemite's landscapes, calculates that an annual confluence of events is needed to set the falls aglow with color. Chief among them:

• Ample melting snow atop El Capitan, which rises 3,000 feet above Yosemite Valley.
• Clear skies near sunset.
• Sunlight angled just so, which typically occurs during 10-day spans twice a year—in late October (though usually too dry to sustain a waterfall) and mid-February.

Frye, as explained in this article, calculates that the ideal viewing window in 2011 is Feb. 12-22. If you want to experience the event in person, expect a crowd. Frye says 2 viewing areas will attract throngs of photographers: the El Capitan picnic area along Northside Drive, and an area along Southside Drive not quite a mile east of the Cathedral Beach picnic area.

Frye has even captured the phenomenon using moonlight. You can see a portion of the great wall of El Capitan in a view provided by Yosemite's Turtleback Dome webcam. Savvy timing, favorable weather and a good viewing angle optimize the Horsetail Fall experience.

As a bonus, we've tossed in a video clip of the waterfall by Yosemite videographer Yosemite Steve (Steve Bumgardner).

Note: The original headline of this post read "The Right Time is Now." To avoid confusing readers who discovered this post at a later date, we have changed the time reference to mid-February. In addition, since this report was first published Yosemite Steve has released a full-length video devoted to Horsetail Fall. It's a beauty.

Michael Frye images on display, top to bottom:
Michael Frye
Horsetail Falls by moonlight
Horsetail Falls at sunset