Flooding in the Sepulveda Boulevard tunnel leading to Los Angeles International Airport set off a chain reaction of problems for people heading to the airport.
Traffic snarled through the tunnel. Some motorists said it took more than an hour to make their way to the other side.
Officials said traffic was expected to begin to flow again after two lanes on the south side of Sepulveda Boulevard reopened.
Travelers scheduled for flights at LAX were asked to judge their arrival times accordingly.
The rain proved to be costly for some store owners along Melrose Avenue in Hollywood.
Storm drains along the thoroughfare were clogged with leaves and debris, leaving some areas resembling a river. The rain water began rising over the curb and spilling into stores.
One business owner reported water reaching the rear of his shop. With his wooden floor and some merchandise damaged, he estimated a loss north of $30,000.
"You could see the water rising past the curb and it was rising fast, too, so we had to get all the stuff out of the window display and put it everywhere else," said Jessica West, an employee in the Dr. Martens store next door. "I didn't expect it to keep rising but it came all the way through to the back of the store."
West said wooden boards and sandbags helped keep some of the water out. The water receded by 5 p.m. after fire crews cleared roadside storm drains.
Stores were looking to rebound from the damage before Black Friday.
The storm also spurred concern about mud flowing off a freeway construction site and going into a neighborhood in Encino.
Heavy downpour backed up a drain in a construction zone and the overflow headed downhill towards homes on Royal Woods Drive.
One home owner said he was told a drain on the 405 Freeway, where crews were installing a sound wall, was blocked and that's what triggered the flow of mud.
A retaining wall prevented runoff from spewing into that home owner's backyard, but residents said they are concerned the saturated hillside may give way if the wet weather gets worse.
It snowed in the mountains above the Grapevine earlier Sunday. It remained cold and damp through the night, but Interstate 5 remained open.
To the east in the local mountains, the day looked more like winter than fall.
The storm that soaked low-lying areas also dumped fresh snow on the Southland's higher elevations and ski resorts. The region could see a good few inches pile up before this storm blows through.