Watch Mother Nature's 'Firefall' optical illusion light up Yosemite National Park

Mother Nature is again putting on a show at California's Yosemite National Park, where every February the setting sun draws a narrow sliver of light on a waterfall to make it glow like a cascade of molten lava.

The phenomenon known as "firefall" draws scores of photographers to a spot near Horsetail Fall, which flows down the granite face of the park's famed rock formation, El Capitan.

Capturing the sight is a challenge. Horsetail Fall only flows in the winter or spring, when there is enough rain and snow.

The sun lights up the fall for only about two minutes at dusk for a few days in February.

Some photographers have had success this year as pictures of the glowing falls are showing up on social media.

#firefall which happens every year in February #yosemite national park pic.twitter.com/LMySjXsmnh

— Krunal Kapadia (@kapadiakrunal1) February 15, 2017

The mesmerizing phenomenon known as a "firefall" has once again illuminated Yosemite National Park... https://t.co/i4Qs3DjS9G pic.twitter.com/9LIkk4x4dv

— UCA ECN (@ecn2016) February 15, 2017

ABD'de Yosemite Milli Parkı, batan güneş ışıklarının şelaleye doğru açıyla gelmesiyle büyüleyici bir doğa olayına ev sahipliği yapıyor. pic.twitter.com/CuOXvde6Eb

— Haberler.com (@Haberler) February 15, 2017

In questi giorni di febbraio le Cascate dello Yosemite sembrano fatte di fuoco https://t.co/4LeeXd3sfn pic.twitter.com/NbbYVeieeV

— Focus (@Focus_it) February 15, 2017

AP