A flood watch is in effect in parts of San Diego County starting at noon Wednesday, according to the National Weather Service.
San Diego County mountains and deserts, Julian, Borrego Springs and Pine Valley are affected by the flood watch from noon through Thursday evening.
Flooding is caused by excessive rainfall. Excessive runoff can result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations.
The NWS recommends those living in areas prone to flooding to be prepared to take action should flooding develop.
Monsoonal moisture can increase with scattered thunderstorms developing in the mountains with some moving into the deserts. Thunderstorms will produce heavy rainfall with flash flooding possible.
