SLO County forecast: Next two weeks brings major shift in weather pattern

After an extended period of dry weather in the heart of our rainfall season — San Luis Obispo County went from Moderate Drought “D2” to Severe Drought “D3” classification according to Thursday’s March 17 U.S. Drought Monitor’s Map — rain showers returned Saturday afternoon and night as a cold front moved southward through the Central Coast.

Strong to gale-force (25 to 38 mph with gusts to 50 mph) post-frontal northwesterly winds and clearing skies are forecast on Sunday into Monday. High temperatures over this period will range between the high 60s to the mid-70s in the inland valleys (Paso Robles) and coastal valleys (San Luis Obispo). The beaches will reach the low to mid-60s.

On Tuesday, increasing high pressure and gusty Santa Lucia (northwesterly) winds will produce clear skies and warmer temperatures. Many Central Coast locations should reach the low to mid-80s on Tuesday and Wednesday, 10 to 15 degrees above average for late March. These forecasted highs are near or above daily records.

The marine layer is expected to redevelop in the coastal regions as the winds shift out of the northwest (onshore) on Thursday into Saturday.

A major change in the weather pattern is forecast to develop next Monday and Tuesday (March 28 and 29) as a vigorous low-pressure system and associated cold front produce strong southerly winds and rain throughout the Central Coast. At this time between 0.75 and 1.50 inches of precipitation is expected. Remember, this is a long-range forecast and will probably change, but it is the first credible indication of significant rain for 2022.

Surf report

Strong to gale-force (25 to 38 mph with gusts to 50 mph) post-frontal northwesterly winds will cause a rapid increase in wave height. An 8- to 10-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 12-second period) is expected on Sunday.

This northwesterly (310-degree, deep-water) sea and swell will decrease to 6- to 8-feet (with a 7- to 14-second period) on Monday, further lowering to 5- to 7-feet (with an 8- to 15-second period) on Tuesday through Friday.

Seawater temperatures will range between 51 and 53 degrees through Friday.

This week’s temperatures

LOWS AND HIGHS, PASO ROBLES

LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS

PG&E safety tip

Rain after a dry period releases oil, grease and rubber dust that has accumulated on roadways, creating slippery conditions. Driving too fast is the No. 1 cause of traffic accidents on wet days.

Tragically over the years, first responders, such as California Highway Patrol officers, firefighters, Caltrans highway workers, and Pacific Gas and Electric Co. line crews have been hit by vehicles.

So please, “Slow for the Cone Zone.” One of the most significant hazards for workers along highways is motorists who do not exercise caution while driving through work zones.

John Lindsey’s is PG&E’s Diablo Canyon marine meteorologist and a media relations representative. Email him at pgeweather@pge.com or follow him on Twitter @PGE_John.

This story was originally published March 20, 2022 at 5:00 AM.