This video was created by our friends at the NWS office in San Diego, California as part of the 2023 Monsoon Awareness Week. Here, the San Diego office discusses what will be covered this week.
Debris flows are dangerous land and water flows caused by heavy rainfall in areas of steep terrain and loose-bare soil. Flash flooding and debris flows are common in or near wildfire burn scars, so unfortunately many areas within the American Southwest are susceptible to their impacts.
Burned soil can be as water repellant as pavement. When vegetation is burned at high intensity, water-repelling compounds are vaporized and then condense on the soil layers below which prevents soil from absorbing water. This leads to excessive runoff whenever rain falls, resulting in flash flooding and the development of debris flows. Accumulations of ash, soot and burned logs are just a few of the things that wildfires will leave behind, and this debris can quickly move downstream and create a pathway of damage when flooding occurs. #Monsoon2k23
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National Weather Service
Weather Forecast Office
Grand Junction, CO
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