LOS ANGELES (KABC) -- Even as Southern California continues digging out from the recent massive winter storms, more rain is on the way.
An atmospheric river is combining with a low-pressure system over the ocean to bring heavy rain to California.
It will hit first - and heaviest - in Northern California starting Thursday. As the system works its way down south it will lose some of its power, but still drop a healthy amount of precipitation on Southern California Thursday and Friday. From 0.5 to 1.5 inches are expected in various communities.
The skies will clear up in time for Oscar Sunday, but then another system arrives midweek, bringing even more rain.
Unlike the recent blizzard, this system is accompanied by warmer temperatures, meaning snow will only fall at the highest elevations in the mountains.
"It's warmer and that's why the lower elevations are very critical right now where they have snow pack," said Paul Pastelok, a senior long-range meteorologist with Accuweather. "You got the melting and the rain combined. The last couple of ones we had more cold air involved so we didn't see as much flooding. But these next two are a big problem going forward."
Latest forecast for Southern California.
But with snow from the last storm still piled high in the mountains, concerns are growing about the rain combining with snowmelt to generate flooding, especially in the mountain canyons with creeks that could overflow.
"Those collector creeks that are capturing all that snowmelt and rainfall at the same time are going to be seeing some of the highest flows we've seen in some time," said Brett Sanders, a climate engineering expert at University of California Irvine.
The good news is the recent storms have made a significant impact on California's drought status.
"We have seen a pattern that is very favorable to end this drought and that's what we've been looking for for years right now and it's amazing," said Pastelok.
A flood watch has already been issued for communities around San Luis Obispo and Santa Barbara counties. The National Weather Service says flooding is possible from Thursday afternoon through late Friday night.
Current flood watches and weather alerts can be viewed here.
See flood safety tips from the National Weather Service.