SANTA BARBARA, Calif. >> Motorists were stranded in their vehicles on flooded roadways in typically idyllic Santa Barbara on Thursday, while nearby Oxnard got a month’s worth of rain in a single hour in a storm that pummeled Southern California while Christmas travel got underway.

The downpours targeted Ventura and Santa Barbara counties northwest of Los Angeles County overnight, swamping areas in the cities of Port Hueneme, Oxnard and Santa Barbara, where a police detective carried a woman on his back after the SUV she was riding in got stuck in knee-deep floodwaters.

Between midnight and 1 a.m., the storm dumped 3.18 inches (8.08 centimeters) of rainfall in downtown Oxnard, surpassing the area’s average of 2.56 inches (6.50 centimeters) for the entire month of December, according to the National Weather Service.

The deluge prompted flash flooding in Ventura County around 1:30 a.m., the weather service said. Later in the morning, streets began filling with water in parts of Santa Barbara as the storm delivered another deluge. By midday, the rain and wind had eased and residents ventured outside to look at the damage.

Sven Dybdahl, owner of olive oil and vinegar store Viva Oliva in downtown Santa Barbara, said he had trouble finding dry routes to work Thursday morning, but most of the heavy rains and flooding had receded shortly before 11 a.m. He said he was grateful that the weather is only expected to be an issue for a few days at the tail end of the holiday shopping season, otherwise he’d be worried about how the rains would affect his store’s bottom line.

“It will have an impact but thankfully it’s happening quite late,” he said.

By late afternoon, the city of Port Hueneme had lifted evacuation orders for residences on four streets. About 60 houses were affected by the orders, all in a senior citizen community, said Firefighter Andy VanSciver, a Ventura County fire spokesperson. An evacuation center was set up at a college gymnasium.

Three people from the senior community were taken to hospitals out of an abundance of caution, and there were multiple rescues of drivers from flooded vehicles, he said.

The city of Oxnard said in a social media post that many streets and intersections were heavily impacted. “Please stay off the city streets for the next several hours until the water recedes,” the post said.

“This is a genuinely dramatic storm,” climate scientist Daniel Swain, of the University of California, Los Angeles, said in an online briefing. “In Oxnard, particularly, overnight there were downpours that preliminary data suggests were probably the heaviest downpours ever observed in that part of Southern California.”

The National Weather Service issued a tornado warning for Oxnard and the city of Ventura at 1:28 a.m. due to a high-intensity thunderstorm, but no tornado activity was immediately observed, the Ventura County Sheriff’s Office said in a social media post.

Hours later at Heritage Coffee and Gifts in downtown Oxnard, manager Carlos Larios said the storm hadn’t made a dent in their Thursday morning rush despite “gloomy” skies.

“People are still coming in to get coffee, which is surprising,” he said. “I don’t think the rain is going to stop many people from being out and about.”

The storm swept through Northern California earlier in the week as the center of the low-pressure system slowly moved south off the coast. Forecasters described it as a “cutoff low,” a storm that is cut off from the general west-to-east flow and can linger for days, increasing the amount of rainfall.

The system was producing hit-and-miss bands of precipitation rather than generalized widespread rainfall. Forecasters said the low would wobble slightly away from the coast on Thursday, drawing moisture away and allowing some sunshine, but will return.

The San Diego-area weather office warned that rather than fizzling, the storm was gathering energy and its main core would move through that region overnight through Friday morning.

Meanwhile, Californians were gearing up for holiday travel and finishing preparations for Christmas. The Automobile Club of Southern California predicted 9.5 million people in the region would travel during the year-end holiday period.

The Northeast was hit with an unexpectedly strong storm earlier this week, and some parts of Maine, New Hampshire and Vermont were still digging out from rain and wind damage. Parts of Maine along the Androscoggin and Kennebec rivers were hit especially hard.

Floodwaters were receding throughout northern New England, though some localized areas were still in the flood stage, said Jon Palmer, a meteorologist with the National Weather Service. Flood warnings were also still in effect in parts of Maine and New Hampshire, he said.

At least five people in East Coast states have died in the storms, with deaths reported in Pennsylvania, New York, Massachusetts and Maine.

The storm cut power to 400,000 customers in Maine, and restoration was still underway Thursday morning.

Antczak reported from Los Angeles. Associated Press reporter Patrick Whittle in Portland, Maine, contributed to this report.