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March is a notoriously fickle month for California precipitation, but the storm door remains open for the Golden State, where precipitation has been plentiful for a second straight year. The month began with a severe blizzard, and it looks like it will close with a solid dose of Sierra snow — and a potentially significant rainstorm in Southern California. A trio of spring storms is sweeping into California this week. More than 30 inches of snow fell in parts of the Sierra Nevada over the weekend. A second system, moving through Northern California on Wednesday and Thursday, could drop up to 2 feet at the highest peaks, along with low-elevation rains. The strongest storm in the series, however, is forecast for Easter weekend. The active spring weather caps an El Niño winter that has been volatile at times, with torrential downpours, localized flooding and frequent thunderstorms. Strong weekend storm renews flood concerns A modest system will deliver rain, snow and wind to Northern California beginning Wednesday, with winter storm warnings in effect for a swath of the Sierra Nevada into Thursday. But all eyes are on a strong low-pressure system that is forecast to drop down along the California coast on Friday and send rounds of moisture into the southern half of the state. "It's a slow-moving storm, and it's going to be with us for multiple days," Ryan Kittell, a meteorologist with the National Weather Service office serving Los Angeles, said in an interview. "A cold front moves through Friday and Saturday, and then the low pressure center just kind of spins around over Central and Southern California through Sunday and maybe even into Monday." The storm could deliver 1 to 3 inches of rain on the region's populated coast and valleys and up to 6 inches on the coastal mountain slopes — along with a risk of thunderstorms. Because there is some uncertainty in the forecast, the storm's track could change and precipitation totals could trend up or down. "There are still a number of our projections that are showing double those totals," Kittell said. "If that comes to fruition, it would open up the possibility of more significant flooding." That could include roadway or neighborhood flooding, swift-water rescues and an increased risk of landslides in the region. "Given the state of our hillsides after the heavy rain earlier this season, it's very likely that this storm will create many additional mud and rock slides in the hills and mountains," the Weather Service office in Los Angeles wrote. As much as 3 feet of snow could fall in Southern California's coastal ranges at the highest elevations. The heart of the wet season in Southern California runs from December through March, with rain usually shutting off completely in May. Kittell said that while rainstorms aren't unusual for late March in Los Angeles, the higher-end model scenarios for this weekend would be rare for this time of year. A boost for Sierra snowpack This week's storm train will help to maintain or even add to the big gains in California's snowpack in early March. Statewide snowpack is holding near average for the time of year at 102 percent. The northern Sierra, where most of the state's water is stored, is faring best at 115 percent of average. Incoming storms should further boost those numbers ahead of a key April 1 benchmark: the typical peak snowpack that officials use to gauge water supply for the year. With the additional Sierra snow forecast, California could record consecutive above-average snow seasons for the first time since 2010 and 2011. Last year on April 1, the snowpack was 245 percent of average. Overall, the state's water supply outlook looks rosy for this year, with full reservoirs combined with a healthy snowpack. California's major reservoirs sit at 116 percent of their average levels for the date, largely because of last year's "water miracle." The California Department of Water Resources announced last week that it would double water allocations for this year from the State Water Project. Parts of the Sierra Nevada are still running behind in terms of total precipitation for the water year, though an active storm track over the next week or two should help to close that gap. Daniel Swain, a climate scientist at the University of California at Los Angeles, said that this week's storms would improve Sierra snowpack but not massively increase it. "This has been a pretty good water year … and it looks like March is going to further bolster that picture," he said in a briefing on Monday. "This is not going to be a major drought year in California — it's safe to say — just based on what's already happened."