Sierra Madre issues evacuation warning for latest rain storm

Sierra Madre city leaders issued an evacuation warning in anticipation of the latest rain storm to hit Southern California.

The advisory will begin at 6 a.m. on Wednesday and last until at least 6 a.m. on Friday, March 7. The areas affected by the warning border the Angeles National Forest, which the Eaton Fire razed. 

NWS meteorologists believe this storm will bring moderate to heavy rain and mountain snow between Tuesday and Thursday. 

The city took similar precautions before a storm in mid-February since the Eaton Fire burned much of the vegetation on the hillsides surrounding the area. During the last storm, the National Weather Service said about 3.5 inches of rain fell on the Santa Anita Dam, which is roughly 2 miles away from the city. It filled every debris basin surrounding the city to capacity, causing mud and debris to flow through Sierra Madre neighborhoods.

Contractors have tried to clear the debris in the weeks leading up to this week's storm. However, the city said they have not been emptied, emphasizing that "any significant rainfall" could cause flooding, mudslides and debris flows. Residents in high-risk areas may be trapped for several days if a mud or debris flow happens. 

"Once the flow starts, it is too late to evacuate. If a mudflow occurs, public safety and public works personnel will not be able to enter an active debris flow zone," the city wrote in the message accompanying the evacuation warning. "Please, do not put yourself in that position."

In a report analyzing the region, the Department of Conservation mentioned floods in the same area as the Eaton Fire killed dozens in 1938 and 1969. In 1938, the floods killed 87 people and caused roughly $1.5 billion of damage when accounting for inflation. The 1969 flood was slightly less severe, killing 60 people in Southern California. However, it caused significantly more damage, totaling about $3.4 billion when accounting for inflation.