The fast-moving system was forecasted to build by early afternoon and possibly clear out by evening.
Tuesday, many Southlanders stocked up on umbrellas, jackets and windshield wipers to prepare for the wet weather. There was light rain in parts of Los Angeles County, but it wasn't enough to cause problems.
A green flag alert was in effect for hillside communities prone to mudslides in the burn areas. Also, wind advisories were up for L.A. and Ventura county mountains, as well as the Antelope Valley.
Temperatures Wednesday were expected to top 65 in L.A. and Orange counties, Valleys and the I.E. and linger in the high 60s Thursday with some scattered morning drizzle. For the local mountains, rain and even snow was expected at the 8,000-foot level with highs in the 40s.
The leading edge of the storm crept in from the north Wednesday, making for a soggy morning for those living in Ventura County.
The rain fell at a steady clip, filling up gutters and storm drains, but also caused some closures. The access road leading to the Ventura Pier and San Buenaventura State Beach was closed due to flooding.
In Oxnard, commuters awoke to drenched roads caused by a steady drizzle. Many said they welcome the rain but were not looking forward to driving in it.
"We're taking a road trip in this rain, so it's crazy," said an Oxnard resident. "We heard that later this afternoon, it's going to come down pretty hard, so we're pretty scared."
Another Oxnard commuter, Larry Lopez, said he will be driving slower, being more vigilant and watching for speeders on the road.
The Ventura division of the California Highway Patrol has been busy with weather-related traffic accidents.
"That is by far the biggest problem when we get our first rain. People are just driving too fast, losing control of their vehicles on the wet roadway, and the results are traffic collisions," CHP Officer Steve Reid said.
On the 101 Freeway in Oxnard, a Chevy Suburban lost control on the wet roads and slammed into a retaining wall. A mother and her baby were inside the SUV, but both walked away without any injuries.
Such accidents serve as reminders to take it slow on the roads. This is the first rain of the season, so oils are coming to the surface, creating roads that are slicker than drivers might suspect.
Los Angeles County
Just hours into the first big storm of the season, a fatal rain-related collision occurred in Palos Verdes.
A teenage driver lost control and slammed into a traffic light pole. The driver walked away uninjured, but his 16-year-old female passenger didn't survive.
L.A. County Sheriff's deputies said the driver was heading up the hill on Hawthorne Boulevard at the time. Speed was not a factor, but they said the rain-slicked road was.
"With the rain, it raises oil on the road so your car may be fine for dry traction, but when it rains, it changes things substantially," Sgt. Stanley Bailif said.
Slippery roads aren't the only hazards for driver. Large tree limbs and other fallen debris can make getting around town frustrating and dangerous.
"It's the same message I tell my deputies when they go out every day: you have to slow down, give yourself more distance to the cars and you just have to leave a little earlier if you need to," Bailif said.
In Pomona, a slick roadway may be responsible for a double fatal accident that shutdown all eastbound traffic on the 10 freeway.
Traffic was backed up for miles as the CHP investigated the afternoon collision.
In the Santa Clarita Valley, hours of heavy to moderate rainfall saturated the streets as well.
Slick roads caused fender benders, creating a traffic nightmare on parts of the 5 Freeway running through the valley.
The CHP reported that from 6 a.m. to 8 a.m., there were about 66 collisions in L.A. County.
Many toted umbrellas and bundled up to fight the cooler temperatures that came with the rain.
"I like it's great we've got rain, I just wish it wouldn't be so much," said Santa Clarita resident James Jones. "It's the first one of the season, but it looks like it's going to be a couple of inches of rain in the next couple of hours. I'm just waiting on the bus here, it's been five minutes and I'm soaked."
Wednesday marked International Walk-to-School Day, and school children in Glendale got caught in the rain.
"It's great, kids love it. I think it's the parents that don't like it so much, but the kids are so excited to walk in the rain," said Glendale resident Kara Sergille.
Heavy rain is always a concern in the Southland burn area because they are prone to slides and flooding.
In Sierra Madre, water trickled along roads next to barricades put in place to protect homes from mud and debris flows.
The rainfall hadn't triggered any problems, but foothill residents are always aware of the danger.
"We live right in the foothills in Monrovia and there have been mudslides in our neighborhood," said Amy McConnell.
The storm dumped steady rain over the Inland Empire, with strong and gusty winds by the afternoon.
The CHP issued a traffic advisory for the Cajon Pass because of dense fog and rain.
In Wrightwood, there was a chance for a dusting of snow at night as a storm front moved in earlier
In Devore, residents said they saw heavy runoff get into the streets and sizable puddles forming on the roads.
The steady rain arrived in the morning with a chilly wind just in time for the morning commute. About 3/4 of an inch to 1 inch of rain was expected to fall in the I.E., which could make the roadways slick and dangerous.
The CHP warned drivers to take it slow and leave extra time to get to their destinations. Officials also reminded motorists that any time their windshield wipers are on continuously, their headlights must be turned on as well.
Phelan resident Patricia Waldron said she didn't see many drivers with their headlines turned on.
The Huntington Beach Pier was deserted as driving rain came down in the afternoon.
"It's windy and a lot of rain and when you get wind out here off the ocean, it will really drive people away," said Bud Wescott, who runs a nearby surf shop, adding that he only had one customer by early afternoon.
In the water, only a handful of surfers brave the conditions.
The steady rain at times flooded streets across Orange County and left many people unprepared.
"My umbrella is in the garage," said Yorba Linda resident Anita Hurty with a laugh.