Clear skies and cooler temperatures forecast for SLO County

Last week, the weather pattern looked more like summer than fall, with the Paso Robles Municipal Airport recording six consecutive days of record daily high temperatures.

This string of record triple-digit temperatures in the inland valleys was unprecedented for October, while gentle northwesterly winds (on land) and the sea layer they brought kept beaches largely cloudy and cool.

A series of storms are moving into the Pacific Northwest this week, bringing rain and gale-force winds. Along the Central Coast, these low-pressure systems will push dry cold fronts through our region, creating steep pressure gradients along the California coastline.

These gradients will bring increasing northwesterly winds, cooler temperatures and clearer skies.

From Sunday onwards, a pattern of mild to moderate (8 to 30 km/h) Santa Lucia (northeasterly) winds will develop in the morning, turning from the northwest and increasing to fresh to strong (30 to 50 km/h) during the afternoon /hour) wind speeds. These wind gusts will continue until Tuesday.

This pattern provides cooler conditions and mostly clear skies, with the exception of low marine clouds during the late evening and night and occasional mid to high clouds.

The inland valleys (Paso Robles) will reach the mid 80s, while the coastal valleys (San Luis Obispo) will reach the mid 70s. Beaches will range between the 60s and low 70s, with the exception of Cayucos, Avila Beach and Shell Beach, which will be in the mid 70s.

Strong to gale force winds (25 to 38 mph with gusts up to 70 mph) are expected along the coastline Wednesday through Saturday. These winds will bring a much cooler marine air mass to the entire region, with inland and coastal valleys only reaching the 70s while beaches will be mostly in the 60s.

Next Saturday and Sunday, moderate to fresh (21 to 39 km/h with gusts up to 55 km/h) Santa Lucia (northeasterly) winds will develop, producing clear skies and low relative humidity.

While inland valleys will reach the high 60s during this time frame, coastal valleys and beaches could see temperatures in the low 80s.

The long-range models do not indicate significant rain as the storm remains well north of the Central Coast.

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Steve Wilson swilson@star-telegram.com

Surf report

Seas and swells of 8 to 8 feet northwest (295 degrees deep water) are forecast along our coastline through Wednesday morning, with 2 to 3 feet of swell (with a period of 7 to 12 seconds). – up to a period of 14 seconds) from Wednesday afternoon to Friday.

A northwesterly (300 degree deep water) sea and swell (with a period of 5 to 13 seconds) is forecast this Saturday and Sunday.

A very long period (high energy) northwest swell is expected next week.

Combined with this northwest swell, there will be a 1 to 3 foot swell in the Southern Hemisphere (205 degrees deep water) Sunday through Tuesday (with a period of 15 to 17 seconds).

Sea surface temperatures will be between 61 and 63 degrees through Tuesday. Increasing amounts of upwelling will lower sea surface temperatures to 53 to 57 degrees Wednesday through next Saturday.

On this date in weather history (October 13)

1846: A major hurricane passed over Cuba, Florida, Georgia, North and South Carolina, Virginia and Pennsylvania. The hurricane caused extensive damage along its entire path, which was similar to the path of Hurricane Hazel 108 years later. The hurricane caused extensive damage near Key West in Florida. In Philadelphia it was the most destructive storm in thirty years. (David Ludlum)

2009: One of the most intense weather systems I saw during the month of October brought stormy weather along the entire Central Coast. A 966 millibar low pressure system off the Oregon coast and associated cold front produced heavy rain and fresh gale to strong gale to strong gale (39 to 54 mph) southerly winds along our coastline and moderate gale to fresh gale (32 to 46 mph) winds in the coastal valleys.

Total number of precipitations per 24 hours:

• Diablo Canyon Ocean Lab, 2.48 inches

• SLOweather.com, 7.55 inches

• Vista del Lago in San Luis Obispo, 6.88 inches

• Cottontail Creek in Cayucos, 5.55 inches

• More from Lopez, 4.13 inches

• Highway 41 between Morro Bay and Atascadero, 9.25 inches

• Highway 41 at Toro Creek “Paul’s House”, 19.8 cm

• Cambria Fire Department, 3.66 inches

• Paso Robles Municipal Airport, 1.85 inches

2020: The morning wind coming from the Santa Lucia Mountains produced some interesting temperatures. At 5:53 a.m., the Paso Robles Municipal Airport reported 49 degrees, while Cal Poly was 85 degrees.

This week’s temperatures

LOW AND HEIGHT, PASO ROBLES

LOW AND HIGH, SAN LUIS OBISPO AND COASTAL VALLEYS

John Lindsey is a retired PG&E marine meteorologist. Email him at JohnLindseyLosOsos@gmail.com or follow him on Twitter @PGE_John.