No relief in sight for dry December in San Luis Obispo

This December will go down as the fourth driest on record in San Luis Obispo County weather history.

It will finish as one of the coldest Decembers as well.

John Lindsey, a private forecaster who has monitored Central Coast weather for more than two decades, said only 0.18 inches of rain has fallen this month at Cal Poly, where the city’s climatology records have been kept since 1948. No rain is forecast for today or Saturday, either.

Only two other years — 1999 and 1963 — had less rainfall. The driest December ever occurred in 1989, when there was no rain. The fifth-driest December was 1990, when 0.43 was measured.

December is normally a reliable month for rain. The historical average is 3.79 inches in San Luis Obispo, making December a key part of the region’s rainy season, which runs from December through March.

Hope that the area might get decent rain this winter is not yet lost.

Lindsey, a media relations specialist with PG&E, discovered in reviewing the records that after three of the five driest Decembers, major rains developed to help boost the annual total.

“The December of 1990 was followed by 12.82 inches of rain in March of 1991 (miracle rains of March),” Lindsey wrote in an email. “The December of 1999 was followed by 13.17 inches of rain in February of 2000. The December of 1963 was followed by 3.56 inches of rain in January, 8.08 inches of rain in February, 4.61 inches in March and 3.84 inches in April, 1964.”

Even so, the forecast for today and the holiday weekend is for dry, warm weather, with nary a rain cloud in sight.

Fog may hug the coastline this morning, but otherwise clear skies will prevail. High pressure then builds over the county Saturday, making for a sparkling-clear New Year’s Eve and first day of the new year.

The high in San Luis Obispo today will be 70 degrees, warming to the mid-70s possibly this weekend. Paso Robles will also be in the upper 60s to near 70 today through the holiday period.Lindsey said rain could finally make its way into California later next week, but only as far south as Monterey.

In looking at temperatures, Lindsey said this December will be the coldest since 1990. The month had been trending to be the coolest since 1971, but this week’s warm up has pushed up the average temperature for the month to 50.3 degrees (with the highs and lows added together and then averaged), compared to the normal average of 53.3.