Weather Watch

Who needs Groundhog Day. Central Coast’s furry sea mammals are the best meteorologists

Government and private meteorologist, scientists, engineers, programmers and technicians collect incomprehensible amounts of atmospheric and oceanographic data from satellites, marine buoys, aircraft, ships, ground weather stations and weather balloons and input of all of it in some of the most powerful computers on earth to initialize numerical models with the uniting goal to protect life and property.

A noble and righteous undertaking indeed!

Without a doubt, the weather models have vastly improved over the years, a quiet revolution that hasn’t been noticed much outside the meteorological community. With that said, there’s a hairy prognosticator — in fact, one of the furriest creatures of all at around one million hairs per square inch — of oceanographic and atmospheric conditions.

It’s not Punxsutawney Phil who emerges from his hole to predict how much longer winter will last or male tarantulas that surface from their dens in fall to look for a mate. It’s the sea otter (Enhydra lutris) that lives along the Central Coast, and here’s why.

While attending a U.S. Navy oceanography class many years ago, a salty old master chief told us about a scale we could use while flying above the ocean to gauge wind speeds from the appearance of waves and swells. In the early 1800s, British Rear Admiral Sir Francis Beaufort devised the Beaufort scale, which is a clear and concise way to determine wind speed that could also be used by landlubbers.

I lovingly used this scale today in the PG&E Diablo Canyon Weather Forecast to convey wind speeds. With that said, the Beaufort Scale will tell you what is presently occurring.

However, another observational scale will give you an idea of what could happen in the future, and I call it the “Diablo Canyon Otter Scale.”

I’ve been forecasting oceanographic and atmospheric conditions at Diablo Canyon Power Plant for over 27 years, and I observed that well before a big storm slams into the Central Coast, larger than usual numbers of sea otters would gather in the Diablo Canyon Marina.

Over the decades, I can almost judge the ferocity of a future storm by how many sea otters congregate in the marina. If it’s between five or 10 otters, the storm will be moderate; if it’s 10 to 20 otters, the tempests will be strong; if it’s over 20 sea otters, the storm will be severe.

That’s what occurred before the Jan. 17 storm. I sent out a tweet that contained a video that showed sea otters gathering in the Diablo Canyon Marina on Jan. 16. The next day, a vigorous cold front moved through the Central Coast with gale-force southerly winds, heavy rain and thunderstorms.

Calvin French reported 3.6 inches of rain in Adelaida. Long Valley Ranches in Atascadero had 4.4 inches. reported a rain rate of 5 inches per hour. The sustained southerly winds at Diablo Canyon reached 43.6 mph with gust to 54.1 mph.

Most importantly for the sea otters, the westerly swell at the Diablo Canyon waverider buoy stationed about a quarter of mile southwest of the marina’s breakwaters peaked at 17.2 feet with an 18-second period at 3 p.m. Jan. 17, while the Santa Lucia Escarpment waverider buoy about 45 miles to the southwest of Diablo Canyon reached 25 feet at 4 p.m.

Yet, conditions in the eastern part of the marina were the otter remained stayed relatively calm. During these severe storms, you can hear the little high-frequency cries of the sea otter puppies to their mothers.

No sea otter would want to be in conditions like that foraging for food. You see, sea otters need to eat between 20 and 25 percent of their body weight a day, even more if they are nursing, to support their extraordinarily high metabolism rate. Unlike other marine mammals, like harbor seals, sea lions or elephant seals, they don’t have a thick layer of blubber to insulate them from the frigid waters but rely on one of the densest coats of fur in nature to protect them.

How they can foretell, the velocity of a storm is a mystery to me.

The otters probably sense the direction and speed of the prefrontal winds, the velocity of the ocean currents, the surge of the long-period forecast forerunner waves, the length of the day (is it winter or summer) or feeling a drop in atmospheric pressure, all good indicators of a future storm along the Central Coast.

Regardless of how they do it, they are darn good storm forecasters; they need to be, their lives depend upon it.

John Lindsey’s column is special to The Tribune. He is PG&E’s Diablo Canyon marine meteorologist and a media relations representative. Email him at or follow him on Twitter: @PGE_John.
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