The dazzling firefall of Yosemite has returned

The rare and stunningly beautiful phenomenon only occurs during a two-week window in February.

While winter in Yosemite National Park offers a spectacular opportunity to witness the national park's unparalleled beauty, there's one phenomenon in particular worth planning a trip around.

During the last two weeks of February, the angle of the setting sun transforms the 2,130-foot Horsetail Falls into what many have nicknamed "The Yosemite Firefall." The effect is so convincing that it almost appears as if lava is pouring out of the granite cliffside. For photographers, this spectacle is not to be missed, with many snatching up the best spots to catch the phenomenon as early as 5 a.m. each morning.

"The zeitgeist of it all, the social media, the viral nature of this year's photography played a huge role in (the crowds)," Bay Area photographer Sean Flansbaum told the SFGate in 2016. "I wouldn't say it was out of control, but it became really kinda fevered. It spread like a wildfire, in terms of the popularity."

Like any other weather-dependent event, the enthusiasm over the natural phenomenon can quickly lead to disappointment when the setting sun is stymied by storms, clouds or fog. Some years, the firefall has failed to show at all during the critical two-week window.