San Francisco set a new October high tide record Saturday when a gauge at Crissy Field recorded a water level 1.62 feet above the average highest daily tide.
The previous record high October tide of 1.4 feet was set just last year. The observed water level was also more than 0.2 feet higher than the National Weather Service forecast.
October typically has the least extreme tides of the year due to gravitational alignments of the moon and sun, but Saturday’s tide was in the range more typical of winter king tides. El Niño is fueling record-breaking sea surface temperatures off the coast of California. Warmer-than-normal water takes up more volume and pushes tides higher, a process known as thermal expansion…