A Flash Flood Watch has been issued for the Imperial Valley.

The National Weather Service forecast calls for a 20% chance of rain after 10:00 p.m. Christmas night. The forecast for Thursday ups that to a 100% chance of precipitation with new rainfall amounts of between a half and three quarters of an inch possible. The NWS says the Flash Flood Watch is in effect from late Wednesday through Friday morning. A strong low pressure system will move into southern California resulting in periods of moderate to possibly heavy rainfall with the heaviest rainfall late Thursday morning until Thursday night. Areas affected include the southeast corner of Imperial Valley , Ocotillo , Plaster City , Desert Shores , Salton Sea , Palo Verde Valley and then moving eastward into the Colorado River valley and Yuma area. A Flash Flood Watch means that flooding of washes , creeks and other drainage areas is possible. Temperatures Thursday will reach a high of just 55 degrees with an overnight low in the mid-forties. Friday will see a 30% chance of rain before 10:00 a.m. and a high temperature near 62. Overnight temperatures through the weekend will dip into the mid-thirties.