The first significant storm of the season brought snow and downpours to Southern California that doused wildfires and caused some ash and mud to flow across streets in the Los Angeles area on Monday.

Forecasts say the chances of flash flooding are not high, but even so, city crews are reinforcing roads and telling residents to take warnings seriously.

With parts of Los Angeles County still smoldering from wildfires, the expected rain this weekend would seem like a welcome relief. But how the rain falls could make the difference between a disaster respite or a disaster repeat.