US: Flash flooding and evacuations for Butte county (California) November 29 /update 13

Event

Authorities issued mandatory evacuation notices for portions of Butte county (California) during the afternoon hours (local time) on Thursday, November 29, due to flash flooding and debris flows near the so-called Camp Fire burn scar. Evacuation orders include areas from Honey Run road to the Skyway. Flooding also closed lanes on CA-99. Heavy rain of 2.5-5 cm (1-2 in) fell within an hour near Chico and Paradise, resulting in debris flows in creek beds out of the burn scar area. The US National Weather Service (NWS) flash flood warning is in effect until 21:30 on Thursday. Further flooding, evacuations, and road closures are possible.

Context

California regularly experiences wildfires from May through November and this year had some of the largest and deadliest fires in the state's recorded history. As of November 11, 7579 fires have burned roughly 675,000 hectares (1,668,000 acres), including the Camp Fire near Paradise, which was the most destructive and deadliest in the state’s history. 

Due to a lack of living vegetation and the presence of ash, mudslides and debris flows are common during rainstorms following the wildfire season.

Advice

Individuals in Butte county are advised to monitor developments to the situation, adhere to instructions by local authorities, anticipate transportation disruptions and flash flooding, and avoid low-lying areas downhill from burn scars. Remember that walking and driving through running water can be dangerous - 15 cm (6 in) of running water is enough to knock over an adult.