More storm to hit weather-battered U.S. California

LOS ANGELES, March 21: (Xinhua) — Another major storm system is set to batter California this week as scattered showers started in the southern part of the western U.S. state on Monday. The powerful storm will likely bring heavier rain, very strong winds and snow to the area late Monday night through Wednesday, according to the U.S. National Weather Service (NWS). High surf and hazardous seas are also expected in the Tuesday to Wednesday time frame, according to NWS Los Angeles.

California has already been hammered by at least 11 atmospheric rivers this season, which brought heavy rainfall, snowfall, flooding and landslides, among other damages. The latest atmospheric river, which struck the state last week, left soil overly saturated and vulnerable to new flooding and rapid runoffs, according to the NWS. An atmospheric river is a long, narrow band of tropical moisture that gets carried along mid- and upper- parts of the atmosphere.

When these systems move over land, they can produce intense rainfall rates and strong winds. Colder atmospheric river systems can also produce significant snow at higher elevations. According to the U.S. National Oceanic and Atmospheric Administration, atmospheric river storms account for 30 percent to 50 percent of annual precipitation for the U.S. West Coast on average.