As Californians can tell by the already beige hills, the early fire weather warnings and the dusty umbrellas sitting deep inside closets, it’s been drier than usual this winter. And according to decades worth of precipitation data, that’s the new normal. What’s considered “normal” for baseline rainfall amounts is determined by a 30-year average that gets recalculated every decade. The latest recalculation, according to Jan Null, a forecaster who runs Golden Gate Weather Services, “show a noticeably drier state” through 2020 compared to the previous “normal” calculation covering 1981 through 2010.
- The New York Times: There’s a New Definition of ‘Normal’ for Weather