The National Weather Service has issued a Flash Flood Watch ahead of a cold front that is expected to bring heavy rainfall to the area.
Heavy, brief downpours and the possibility of a thunderstorm are possible with rain rates that could reach one-half inch per hour, NWS officials said.
The Flash Flood Watch is in effect until 6 a.m. Wednesday for areas including the San Gabriel Valley.
Residents who live below recent burn areas are advised to take the necessary steps to protect their lives and property and to follow the instructions of emergency preparedness officials.
Forecasters predict a 100 percent chance for rainfall overnight with a 90 percent chance for rain to come before 10 a.m. Wednesday. The threat of rain will diminish into the night.