A three-week winter dry spell left the California snowpack at just 83 percent of average, snow surveyors found Tuesday, a setback for the state as it tries to break out of record drought. Californians depend on snowfall for a third of their water, and hoped a strong El Niño system would deliver heavy snow and rain. After a wet December and January, sunshine and blue skies returned, bringing temperatures in the 90s to Southern California last month. The state last year had its driest four-year spell on record, leading Gov. Jerry Brown to order a 25 percent water conservation target for cities and towns.