More southern Utah flash flooding possible, burn scar debris flows
Jul 29, 2021, 4:16 PM
(Christina Johansen)
SALT LAKE CITY — The National Weather Service is warning of heavy rain in southern Utah Thursday afternoon and evening. Not only does this increase the likelihood of flash flooding, but it also could lead to debris flows along burn scars across the state.
Meteorologist Monica Traphagan says flash flooding is possible around Lake Powell, Capitol Reef and Canyonlands national parks, and Kanab.
“Any thunderstorm that you get, if it moves over the right spot, is capable of creating flash flooding,” Traphagan said. “As we get into later this afternoon and this evening, we should see more coverage there with the potential to impact flood-prone areas.”
Our Southern Utah Flash Flood Potential Rating product is currently out of date on the information webpage. While we work on that, here’s the outlook for popular recreation areas through Friday. #utwx pic.twitter.com/ES4a1I5hrC
— NWS Salt Lake City (@NWSSaltLakeCity) July 29, 2021
All eyes on burn scars
Traphagan says the potential for debris flows along burn scars is also increased when storms drop a lot of rain in a short period.
“When you’ve had a fire over the area, the soil becomes hydrophobic,” Traphagen said. “Those burn scar areas just can’t take as much water….it takes maybe a bit less rain than you’d expect to cause some potential problems.”
We’ve just received a report of 0.78″ of rain in about 10 minutes from a sensor along Main Street in Beaver. These storms are producing extremely heavy rainfall! #utwx
— NWS Salt Lake City (@NWSSaltLakeCity) July 29, 2021
Storms head north Friday
While storms will be scattered across the Wasatch Front Thursday afternoon and evening, heavier thunderstorms move north Friday. And, they’ll be heavy-duty.
“With any storms that develop, they’re capable of producing very heavy rainfall, as well as frequent lightning, some hail, and gusty winds,” Traphagan says.
The KSL Weather Center shows a 60% chance of thunderstorms Friday in the Salt Lake area. That increases to 70% and 80% on Saturday and Sunday respectively.