California rainstorms aid firefighters but bring ash, mud and debris in burn areas

Rain may help firefighters reining in fires after weeks of dry weather but also boosts risk of toxic ash runoff

Rain eased on Monday after southern California's first significant storm of the season brought weekend downpours that aided firefighters but caused ash, mud and debris to flow across streets in wildfire burn areas.

Less than an inch of rain fell in most areas, but it was enough to loosen Los Angeles hillsides burned bare by the recent blaze near the Pacific Palisades, where crews working before dawn cleared inundated roadways including the famed Pacific Coast Highway.

In neighboring Malibu, four schools were closed on Monday due to dangerous road conditions and challenges with access", the Santa Monica-Malibu Unified School District said in a statement.

North of Los Angeles, snowy conditions late on Sunday shut down the mountainous Tejon Pass section of Interstate 5, a key north-south artery. The California department of transportation said there was no estimated reopening time.