NORTH COUNTY — After a week and a half of subtlety shifting forecasts, the low pressure front local meteorologists were monitoring finally brought some rain to the Central Coast late Tuesday night.
As John Lindsey, PG&E’s Diablo Canyon marine meteorologist and a media relations representative, was quick to point out, regardless of how much (or little) water the three-day storm actually delivers, it has been over six months since the Central Coast has seen a significant amount of rain.
Paso Robles received .28 inches of rain, bringing the season total to the same number. Totals for Atascadero were not available prior to publication.
To paraphrase an old adage, do something you love and never work a day, Lindsey is getting set to do something he loves, and seems to do every day, and coincidentally gets paid for. That’s talk about the weather, this time with the Atascadero Rotary Club on Oct. 10. The club’s talks are typically held with a noon luncheon on Wednesdays at the Atascadero Lake Pavilion.
Items he’ll likely discuss with club members and visitors are exactly what this type of rain does after an extended dry period.
“Drizzle and showers aren’t enough to wash off the lines,” he said, noting that while PG&E uses a wide range of equipment from water trucks and helicopters to blast the muck off long distance power lines, local neighborhoods are still subject to debris buildup that can cause arcs and outages.
It’s much the same phenomena that makes driving in the first rain of the season so dangerous, with oil and dirt built up on pavement reducing traction.
While forecasts for this storm initially predicted up to half an inch, that number was revised down to a quarter of an inch as the front drew near. That’s still significant as, he explained, the last good downpour was in April with just under a fifth of an inch registered at Diablo Canyon weather station.
For more of a microclimate angle on the forecast, Lindsey recommended consulting with, “the Oracle of Atascadero,” coincidentally a Rotary member as well, John Neil, general manager of the Atascadero Mutual Water Company.
Neil stumbled across an interesting bit of data in the water company’s 104 years of monitoring at their Salinas River rain gauge, noting that if Atascadero gets two inches during the month of October, there’s usually an above-average rain year, from July 1 to June 30.
Now, he cautions, correlation is no indication of causation or even a guarantee of repetition, but the data point has held steady with 12 matching instances since 1913.
That gauge has registered an average of 17.5 inches with the most recent above-average year 2017 at 29.8 inches.
On the job here for 18 of those years, Neil notes the City is likely in a better condition to manage it if 2018-2019 delivers heavy rains, with drainage improvements completed over the last 20 years, particularly on Portola Road.
“The other thing about the law of averages,” he adds, “is that we’ve had five of the last six years below average so sooner or later we’re due for it to come back up.”
Either way, more data, and more water is required.