'Yosemite National Park is one of the world’s great destinations for photographers. Each year in late February, however, camera buffs converge with a particular urgency: There are just a few days when the setting sun and the position of the Earth’s orbit transform El Capitan’s wispy Horsetail Falls into a spectacular light show. This year’s “fire fall” effect was captured at about 5:45 p.m. Friday as the sun lit up the 1,500-foot waterfall against the darkening granite behind it. '
From what I've gathered through blogs & videos this event is difficult to capture as the intensity of light falling on the fall as well as the water content of the fall makes all the difference! Theres also a particular time when you see it as molten lava, on most other occasions it just brightens up the fall & the surrounding area.
Google Horsetail Falls, Yosemite National Park for more info & images :)
