California is rapidly plunging back into drought, with severe conditions now existing in Santa Barbara, Ventura and Los Angeles counties — home to one-fourth of the state’s population, a national drought monitor said Thursday. The weekly report released by the U.S. Drought Monitor, a project of government agencies and other partners, also shows 44 percent of the state is now considered to be in a moderate drought. It’s a dramatic jump from just last week, when the figure was 13 percent. “It’s not nearly where we’d like to be,” Frank Gehrke, a state official, acknowledged after separately carrying out manual measurements of winter snowfall in the Sierra Nevada mountains, which supplies water to millions of Californians in a good, wet year. Overall, the vital snowpack Thursday stood at less than a third of normal for the date. California lifted a drought state of emergency less than a year ago, ending cutbacks that at the peak of the drought mandated 25 percent conservation by cities and towns, devastated generations of native salmon and other wildlife, made household wells run dry in the state’s…