February in the mark means a lot of visitors to the park trying to capture the glowing light. From the Los Angeles Times:
The natural phenomenon occurs when the waning sunlight strikes Horsetail Fall on the famed rock face of El Capitan. The waterfall is backlighted by the setting sun, creating a streak of orange resembling a lava flow. “Just before and after sunset, it’s glowing like it’s on fire,” a Yosemite ranger once told me.
Maybe the best viewpoint is from a plane: