Glendora officials are warning residents that steady rain expected overnight Monday could produce "light mudflows" in areas affected by the Colby fire.
City officials raised their alert level from green to yellow Sunday in anticipation of the storm system that could deliver up to an inch of rain in hillside areas left bare by the 2,000-acre Colby fire late last year. Earlier this year, residents in Azusa and Glendora were ordered to evacuate as a large storm caused minor debris and mudflows that damaged some properties.
National Weather Service meteorologist David Sweet said a cold front will bring a few hours of steady rain throughout the region Monday night. A low-pressure system will follow that will carry a 70% chance of showers for Tuesday, he said.
The combined storms are expected to add between a quarter-inch and three-quarters of an inch of rain.
Consequently, Sweet said any areas recently affected by burns need to be mindful of the impact that rain can have on land with little to hold it in place.
The yellow-level alert in Glendora triggered rain-related parking restrictions that require residents to remove vehicles, trash bins or other obstructions from the road. However, no evacuation orders are in place and there is no restricted entry into the area, according to a city news release.
The Glendora Police Department will increase patrols in the area to keep “physical presences in the area should the need arise,” the city added.
The affected area includes all properties north of Sierra Madre Avenue, approximately between Yucca Ridge Road and Loraine Avenue, which have the "highest risk" of being affected by flooding and debris flows, according to the city.
Sweet said highs over the next few days stay in the 60s, about 10 degrees below normal. The rain will depart by Wednesday, with temperatures warming over the weekend.