First of two atmospheric rivers, ‘Pineapple Express’, hits California.(Part-1)

Los Angeles — The first of two atmospheric rivers hit California Thursday, causing heavy rain and much-needed snow in the mountains. After stopping cable car operations in the San Francisco Bay Area on Wednesday, the storm reached the south and east. The morning commute in Southern California was hampered by Thursday's rain.

Bob Oravec of the National Weather Service said an atmospheric river, a lengthy band of moisture across the Pacific, was fuelling the storms in Los Angeles and San Diego.

He added atmospheric rivers “typically occur ahead of cold fronts across the Pacific.” And when they meet with West Coast terrain, you get tremendous rain along coastal ranges and inland across the Sierras.” Ruben Gomez cleaned storm drains in his parents' neighborhood Thursday while San Diego rained.

He sandbagged their home, which had been flooded by a previous flood. After the earlier storm swamped the home with six-foot-high water, firefighters rescued his 82-year-old parents. His father was hospitalized for two days for hypothermia and his mother for a week for water in one lung.

“I’ve plugged every hole in the house with plastic and paper to prevent water from rising again,” he claimed. They depend on family, friends, and neighbors for donations without insurance. He is thankful that his parents escaped and are safe in his house in a less flood-prone location.

Last winter, drought-busting atmospheric rivers caused widespread floods, large waves that pounded coastline villages, and record-breaking snowfall that destroyed houses in California. More than 20 perished.

Forecasters expect an even stronger storm on Sunday after this week's “Pineapple Express”—named for its expanse of moisture over the Pacific to reach Hawaii. The California Governor's Office of Emergency Services activated its operations center and deployed personnel and equipment to high-risk locations.

The deputy director of crisis communications, Brian Ferguson, called it “a significant threat to the safety of Californians.” He predicted a 10- to 14-day impact from the Oregon border to San Diego and from the coast to the mountains. “This really is a broad sweep of California that’s going to see threats over the coming week,” Ferguson said.