WASHINGTON COUNTY (ABC4 News) – Zion National Park has been facing flash flood threats this week, with “probable” flash flood potential Wednesday, as park rangers urge visitors to be fully prepared with a backup plan in case of emergency.

ABC4’s Katie Karalis met with Zion National park rangers who said flash floods have claimed several lives in recent years. Seven hikers who entered a slot canyon called Keyhole Canyon in September 2015 were killed when a sudden deluge of rain filled the area.

These sudden downpours are unpredictable and can rapidly increase water levels in a matter of seconds, leaving visitors scrambling over rocks and debris in search of higher ground.

Zion National Park ranger Eugenne Moisa told ABC4 News that some of Zion’s most dangerous flood events in August 2016 and July 2018 took place on days with a seemingly low chance of rain — only 20 to 30 percent.

“It doesn’t necessarily have to be a large storm system,” Moisa said. “It can be something small, something isolated that just feeds the right channel and ends up coming towards us.”

Park officials said that typically, a day will start off with clear blue skies, then clouds will slowly build with afternoon thunderstorms. Flash floods can occur from storms that are miles away or took place hours before.

Rangers said that if you ever find yourself in a flash flood, don’t ever try to outrun it. Leave your gear and find higher ground as soon as possible.

Here are some flash flood facts and safety tips from the Zion National Park website:

Flash floods are a sudden increase in the depth and speed of water in rivers, streams, or washes due to heavy rain from thunderstorms. Floodwaters carry large debris like tree trunks and boulders. Flash floods can occur at any time in Zion National Park and in the desert southwest.
•Flash floods are unpredictable
•Flash floods can be deadly and death most often occurs from blunt force trauma
•Slot canyons are particularly dangerous 
•You can’t outrun a flash flood
•Flash floods can happen with sunny skies overhead

For your safety, become familiar with the potential for flooding:
•Check the weather forecast and stop by the Visitor Center for up to date information
•Watch for changing weather and a buildup of clouds
•Heed warnings
•Be aware of areas that are likely to flood and avoid those areas
•Have a plan in case you encounter a flash flood
•Leave an itinerary with someone and check-in when you are done

Become familiar with the flash flood potential rating system:
Not Expected: Flash flooding is not expected. Your safety is your responsibility.
Possible: Some slot canyons, dry washes, and small streams may
experience flash flooding.
Probable: Some slot canyons, dry washes, and small streams are
expected to experience flash flooding.
Expected: Many slot canyons, dry washes, and small streams are
expected to experience flash flooding.

Become familiar with signs of impending flash flood:
•Surge in water
•Change in water color
•Roaring water sound
•Increased debris in the water

During a flash flood:
•Stay out of the water-do not attempt to cross or enter the water
•Six inches of water can knock you off your feet
•Stay as high as you can and be patient. It can take hours for floodwaters to recede
•Flash floods happen quickly so react quickly. Head for higher ground immediately. DO NOT take time to pick up your gear

For current information on flash flood risk, check the National Weather Service forecast.