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Central California Coast Debris Flows - January 2021

July 22, 2022
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An atmospheric river (AR) moved into California late on the evening of January 26, 2021, bringing intermittent heavy rainfall that resulted in flooding, debris flows, and heavy snowfall at high elevations. This story map collection uses interactive maps, photographs, and rainfall data to tell the story of debris flows in four 2020 burn areas along the central California Coast during the atmospheric river event.  Events highlighted in this collection occurred in the River, CZU Lightning Complex, Dolan, and Carmel burn areas.  

tan pickup truck surrounded by mud and rocks up to the top of the door
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On Sunday, August 16, 2020 at approximately 3:00 PM PST, the River wildfire ignited in Monterey County, California, just west of the Salinas River Valley. The fire burned 20 square kilometers prior to containment on September 4, 2020. Debris-flow deposits at the Chualar and Limekiln sites within the River Burn area were observed on Wednesday, January 27, 2021, and were likely triggered by rainfall events in the early morning hours of January 27, 2021.

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