“Pineapple Express” storm to hit California raises heavy rain, flooding concerns
Inmate firefighters clear snow from the roof of a restaurant in Lake Arrowhead, California, on March 7. Photo: Kyle Grillot/Bloomberg via Getty Images
An atmospheric fluvial event is making its way to Northern and Central California and is expected to arrive Thursday and last through Friday.
Why it matters: This will be a milder storm than the series of storms that have hit the Golden State in recent weeks, bringing rain over snow even at mid-to-high elevations. With a near-record snowfall, posing flood risks.
Threat level: Central coastal California and the central interior valleys could see several inches of heavy rain and a persistent threat of flooding through much of next week, NOAA’s Weather Prediction Center said in a forecast discussion. in the Internet.
Rain on top of snow at about 6,000 feet is likely to cause flooding, including streams and rivers, and waterlogging of homes and businesses could lead to structural damage. Over a foot of snow will be possible for parts of the Cascades and Sierra.
State of the Game: The Pineapple Express storm is pulling moist air from subsoils near Hawaii.
There’s a trajectory of moving a lot of water vapor up, meteorologist Daniel Swain explained Wednesday. Atmospheric rivers are long, narrow highways of moisture that can travel thousands of miles and are responsible for 30-50% of wet season precipitation across the West. US coast, according to NOAA. They have been remarkably persistent and vigorous so far this winter, with no signs of an imminent weather change to drier conditions.
What we’re looking at: Computer modeling from the Center for Western Weather and Water Extremes is projecting an AR3, or “moderate,” atmospheric river event.
By the numbers: The UC Berkeley Central Sierra Snow Lab has recorded 603 inches of snowfall since Oct. 1 as of Wednesday, qualifying as its fifth snowiest year on record.
Worth noting: California’s surprisingly thick snowpack for this time of year has raised hopes for more abundant water supplies and a less active fire season across the state.
But so much snow sitting in the lower elevations is also a concern this week. The dramatic swing from historically dry to very wet conditions in parts of California is consistent with what climate studies show will happen more frequently and more severely in the coming decades.
Meanwhile, the San Bernardino and San Gabriel mountain ranges received enough snow to trap people indoors behind mountains of snow.
Big Bear City received more than 6.6 feet of snow in one week — the most since records were tracked. In nearby Lake Arrowhead, many roads were plowed for the first time in 10 days on Tuesday. The heaviest rains from this upcoming storm are expected to fall north of these areas.