Pineapple Express expected to bring rain to High Desert

Rene Ray De La Cruz, Victorville Daily Press
Updated ·5 min read
12

An atmospheric river known as a Pineapple Express is expected to bring heavy to light rain showers to the High Desert this week, followed by a second round early next week.

The storm should move into Southern California on Thursday and Friday, followed by a partially dry weekend and wet Monday, the National Weather Service reported.

While there is a lot of uncertainty in exact rain amounts, there is a solid 95% chance of at least one half inch in the High Desert and a 70 to 85% chance of at least 1 inch for the coastal areas, valleys, and mountains.

In the High Desert, estimates show that Thursday looks to be the wettest day of the storm. Localized flooding and a slick morning commute will be the greatest impacts, the NWS said.

San Bernardino County Fire officials announced a countywide floodwatch starting Thursday morning. They also urge citizens to prepare for the storm, which includes obtaining sandbags.

Saturday morning through Sunday “may end up being mostly dry, but we'll have to see how the timing evolves over the coming days,” weather officials stated.

Strong winds are also expected in the High Desert on Thursday and Friday, according to the weather service.

A winter storm watch has been issued for portions of the San Bernardino/Riverside County Mountains from 5 a.m. Thursday to 4 p.m. Friday.

Snow levels look to start between 6,500-7,000 feet, but then crash to 4,500-5,000 feet later Thursday afternoon. Light snow expected in San Bernardino Mountains, the NWS reported.

Temperatures from Thursday to Sunday should range from the low 20s to the low 50s in places like Apple Valley, Hesperia, and Victorville.

Often called the Pineapple Express, the atmospheric river picks up moisture in the tropical Pacific around Hawaii, then pushes it toward the West Coast, according to the National Ocean Service.

Northern, Central California to be hit with heavy rains, winds

Over the next several days, a pair of storms is set to blast northern and central California with a nasty, disruptive mix of rain, snow and wind, with the first one arriving on Wednesday and the second likely by Sunday.

Both will be fueled by atmospheric rivers, plumes of tropical moisture that can bring a “firehose” of rain to the state. This type of atmospheric river is sometimes called the “Pineapple Express,” since it originates near Hawaii, according to Weather.com.

The National Weather Service warns that the moisture “will create heavy rain over California.” In fact, rain from the storm is forecast to be heavy enough to trigger flooding, mudslides and cause major travel disruptions across the state, AccuWeather meteorologist Alex Sosnowski said.

Some higher elevations in the mountains could see up to four feet of snow, the weather service says.

The storm will create significant disruptions for travel across much of the state from Wednesday through Thursday as the rain spreads south, AccuWeather senior meteorologist Heather Zehr said.

San Francisco and Sacramento will see downpours on Wednesday, while Los Angeles and San Diego will see the heaviest rain on Thursday.

Strong winds and rough surf will also batter the state, forecasters said.

Flood watches in effect

The heavy rain will create mainly localized areas of flash flooding, the weather service said, with urban areas, roads, small streams, and burn scars the most vulnerable areas. Flood watches have been hoisted for portions of central and northern California.

According to the weather service, portions of central and northern California will see impacts including:

  • Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations.

  • Creeks and streams may rise out of their banks.

  • Flooding may occur in areas with poor drainage and urban areas.

  • Storm drains and ditches may become clogged with debris.

Snowfall in the mountains

While lower elevations see rain, mountainous areas will see snow – and lots of it:

“Major to extreme winter storm impacts are expected in the Sierra Nevada above 6,000 feet Wednesday evening through Thursday night due to snow load and snow amounts up to four feet,” the weather service forecast office in Hanford, California said.

“Travel could be extremely difficult or nearly impossible,” the weather service said. As a result, travel is not advised.”

However, according to Sosnowski, once the snowstorm blows through, “skiers and snowboarders will welcome the snow, and it could be a good weekend to head to the resorts.”

Made visible by clouds, atmospheric rivers are ribbons of water vapor that extend thousands of miles from the tropics to the western U.S. At 250 to 375 miles wide, they provide the fuel for massive rain and snowstorms that can cause flooding along the West Coast.

In general, atmospheric rivers pick up water vapor from the warm, moist air of tropical regions and then drop the water over land in cooler regions as rain or snow.

Another storm Sunday?

Another storm is forecast to hit much of California with low-elevation rain and mountain snow from Sunday to Monday, AccuWeather said. And according to Weather.com “details are still a bit uncertain, but it will also have the potential to bring flooding rain, landslides and rockslides as well as mountain snow and strong winds.”

The weather service says that the next storm will also impact much of the Southwest, including Las Vegas, where Super Bowl week festivities will be underway by Monday. Although the big game is still another week away, since Allegiant Stadium is a dome, rain wouldn’t impact the game itself.

USA TODAY Network contributed to this report.

Daily Press reporter Rene Ray De La Cruz may be reached at 760-951-6227 or RDeLaCruz@VVDailyPress.com. Follow him on Twitter @DP_ReneDeLaCruz.

This article originally appeared on Victorville Daily Press: Pineapple Express expected to bring rain to High Desert