Drier conditions with reduced groundwater recharge and stream discharge are expected in the future, as well as increased flow variability and instability. Projected declines in overall rainfall, increased magnitude of precipitation extremes (rainfall and drought), and increases in air and ocean temperatures are expected to contribute to changed stream flow regimes, including shifts in potential evapotranspiration, rates of infiltration, and onset and duration of surface runoff. Increased air temperatures and reductions in coastal precipitation have already reduced median base flow by 23%. The number of dry days between storms is projected to increase, leading to more frequent and severe drought, and more days with low or no flow conditions.