The world’s atmospheric and climate scientists, oceanographers, meteorologists and countless others spend enormous amounts of resources and work to predict whether the rainfall season will be above or below average.
These are some of the smartest people I know from institutions like the National Oceanic and Atmospheric Administration’s Climate Prediction Center, NASA’s Jet Propulsion Laboratory in Pasadena, Scripps Institute of Oceanography in La Jolla and the Navy’s Fleet Numerical Meteorology and Oceanography Center in Monterey.
Scientists, engineers and technicians analyze and dissect information from oceanographic cycles like El Niño, La Niña, the Pacific Decadal Oscillation and other phases. They collect unfathomable amounts of atmospheric and oceanographic data from satellites, aircraft, ships, ground weather stations and weather balloons and input of all of it in some of the most powerful computers on earth. A daunting task indeed!
Sometimes, however, the answer to the formidable rainfall question is right under our nose. Let me explain.
The Atascadero Mutual Water Company was incorporated in 1913 by Atascadero’s founder, E.G. Lewis, and meets the water requirements of more than 30,000 people. Since 1914, the company has collected rainfall information at a rain gauge at the confluence of the Salinas River and Atascadero Creek, forming a database that contains more than a century of rainfall statistics and well-water levels.
Civil engineer John Neil is the manager of the Atascadero Mutual Water Company and also the president of the Atascadero Rotary Club. Neil loves the science of hydrology and meteorology and their potential impact on people’s lives. For all of us, the five-year drought put into sharp focus the importance of water.
After he carefully reviewed the historical data from this rain gauge, Neil discovered that when the area received more than 2 inches of precipitation during October, the rest of the rain season — which runs through June 30 of the following year — was higher than normal.
In other words, since 1914, the months that follow a wet October over the course of the rain season experience above-average rainfall. Neil calls this the “2-inches-of-rain-in-October rule.” However, in years they record measurable rainfall in July, less-than-average rainfall for the season follows despite what occurs in October.
For the first time since 2010, Neil recorded more than 2 inches of rain last October. As of Friday, their rain gauge has recorded 26.82 inches of rain this season. Normally, they receive 17.42 inches. Cal Poly, the home of climatology for San Luis Obispo, has recorded 33.48 inches, the most rain since the strong El Niño year of 1997-98, when 43.98 inches fell at that location. Rocky Butte, in the San Lucia Mountains near San Simeon, has already recorded 73.63 inches.
I reviewed the rainfall data from the Diablo Canyon Power Plant and other Central Coast locations and noticed the same trend of a wet October leading to near- or above-normal precipitation for the rain season. I must say, I’ve been forecasting weather along the Central Coast since 1992, and my confidence in this oracle from Atascadero has grown considerably. Hopefully, that rain gauge at the confluence of the Salinas River and Atascadero Creek will record more than 2 inches of precious rain this October.
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Despite the record rains this winter, climate change is expected to increase the number of large wildfires as well as the length of the wildfire season in California. To help Californian communities meet this challenge, PG&E launched its Better Together Resilient Communities grant program. Through the program, PG&E will invest $1 million over five years — or $200,000 per year — in shareholder-funded grants to help communities better prepare for, withstand and recover from extreme events and other risks related to climate change. Learn more about the grants and how to apply at www.pge.com/resiliencegrants.
I will be speaking about climate change and weather at the Shell Beach Library (230 Leeward Ave.) at 5 p.m. Wednesday. I would love to see you there.