Horsetail Fall is a seasonal waterfall that only flows in late winter and early spring. For a few days every February, the water turns an igneous orange for a few minutes at sundown.
WATCH: Yosemite firefall: Horsetail Fall brilliantly illuminated as sun sets at specific angle in Yosemite Nat'l Park. pic.twitter.com/6tcfHWJTq6
— NBC Nightly News (@NBCNightlyNews) February 15, 2017
“[The firefall is] this thin ribbon of water just glowing orange with the cliff and the shade behind it, so it just seems like it has its own source of light — that there’s nothing else creating it. It’s really an amazing and beautiful thing to see,” photographer Michael Frye told the National Park Service.
RARE 'firefall' lights up Yosemite National Park: https://t.co/Rp3bZjYLTs pic.twitter.com/lJRXsh1dEE
— The Weather Network (@weathernetwork) February 15, 2017
According to Yosemite, very specific conditions lead to the firefall. Horsetail Fall must be flowing, meaning there can’t be too much snow packed into it. Secondly, the sky must be clear so clouds won’t block the sun’s rays.
'Firefall' optical illusion lights up Yosemite — CNN https://t.co/O5a05j0yp7 #Firefall #StormHour pic.twitter.com/6tfhZbqnoc
— #StormHour (@StormHour) February 15, 2017
This year’s firefall was particularly brilliant. "Last year you couldn't see the fall without a camera lens. This year, from where we're at, you can see the top of the waterfall,” said firefall enthusiast Tom Neumayer.
The return on the #Firefall! Waterfall At Yosemite Turns Into Firefall.
— WeatherNation (@WeatherNation) February 15, 2017
Watch: https://t.co/GtQ9yAD11N pic.twitter.com/ee95aJZ9gm
"The waterfall is bigger than it has been in a long time due to all the rain and snow we have received," said National Park Ranger Scott Gediman.
Rare "firefall" returns to @YosemiteNPS for just a few weeks https://t.co/DSeoRXNtI7 pic.twitter.com/CkAJ7PvWRT
— Travel + Leisure (@TravelLeisure) February 15, 2017
"It has gained popularity the last few years due to social media. People come from all over the world to see this.”
.@YosemiteNPS's "Firefall" is the coolest thing you'll see today https://t.co/YjqRv4XaKA pic.twitter.com/hBOvSXF6IN
— Condé Nast Traveler (@CNTraveler) February 15, 2017
The phenomenon, discovered in 1973, draws hundreds of visitors hoping to catch sight of the fluorescent orange water. "This year, I feel fortunate to have been one of the firsts to witness it," wrote amateur photographer Sangeeta Day in an instagram post. "In fact, I just drove back home after seeing this unforgettable moment."