SPRINGDALE, Utah (ABC4 News) – A strong winter storm is headed to the Southern Utah mountains, hitting five counties the hardest with heavy snowfall and flash flood potential.

With flash flood watches, winter storm warnings, and winter weather advisories in effect starting Tuesday evening, rangers at Zion National Park said they’ll be actively monitoring recent rockfalls to make sure all visitors stay safe.

Park officials said they’re excited that the St. George area’s dry spell — 154 days a without measurable amount of rain — is predicted to come to an end, but they added that they’re also cautious, adding that heavy amounts of rain over short periods of time in slot canyons is a very dangerous combination

As the winter storm comes through, Zion National Park ranger Eleanor Siebers told ABC4 News staff are closely watching the Weeping Rock Area after a massive piece of rock fell from Cable Mountain in August.

“There is now enough debris to cover one football field seven feet deep,” Siebers said. “Think about that. That’s the amount of sandstone that came down that now could potentially be mobilized.”

Flash floods will be possible not only in slot canyons, but also small streams and normally dry washes. Zion National Park is no stranger to deadly flash floods — In 2015, seven people lost their lives when they were caught in a flood while canyoneering in Keyhole Canyon.

“We know that a lot of people are here at Zion on once-in-a-lifetime vacations, but that’s no reason to do something extra dangerous when they really should just wait it out or come next time,” Siebers added.

Park officials said their most recent dangerous flood events took place on days with a seemingly low chance of rain: only 20 to 30 percent.

The flash flood watch will remain in effect until Wednesday evening. During this time, hikers should avoid any trails with slow canyons, such as The Narrows. Rangers say typically if you a flash flood, it’s almost too late to escape — so the number one priority is prevention. If you are caught in one, leave your gear and get to higher ground as soon as possible.