SLO County weather forecast for the week of Nov. 30

Here is this week’s weather forecast from PG&E meteorologist John Lindsey.

A 1,030 millibar area of high pressure over the Great Basin will continue to produce moderate to fresh (13- to 24-mph) Santa Lucia (northeasterly) winds during the night and morning hours through Wednesday, producing cold and crisp mornings and mild afternoons.

Variable mid- to high-level clouds may pass overhead as a weak cold front moves well to the north Monday evening into Tuesday morning.

Monday’s models and charts are advertising a vigorous low-pressure system and associated cold front moving southeast along the California coastline. This cold front will produce increasing southerly winds and rain showers Thursday throughout San Luis Obispo and northern Santa Barbara counties. At this time, the strongest upper-level winds are forecast to remain over Northern California. Consequently, rainfall amounts are forecast to remain below a quarter of an inch, with no rain expected south of Point Conception. However, there’s the chance that the jet stream will shift farther south. This system will bring snow to mountains above 5,000 feet, with several inches possible above 6,000 feet.

Strong- to gale-force (25- to 38-mph) north to northeasterly winds will follow the system as it moves out of the region late Thursday into early Friday, with chilly morning lows and mild afternoon highs, both remaining below-normal for early December. The long-range forecast models show the potential for another low-pressure system to bring rain showers Sunday into next Monday.

Surf report

A long-period northwesterly (305-degree, deep-water) swell from a large Gulf of Alaska storm that developed last week will continue at a 6- to 8-foot level (with a 16- to 18-second period) Monday, increasing to 7 to 9 feet (with a 14- to 16-second period) on Tuesday. This swell will decrease to 4- to 6-feet (with an 11- to 13-second period) Wednesday.

A 9- to 11-foot northwesterly (290-degree, deep-water) sea and swell (with a 7- to 18-second period) is expected along our coastline Thursday, building to 10- to 12-feet (with a 15- to 17-second period) on Friday.

Combined with this northwesterly sea and swell will be increasing southerly (190-degree, shallow-water) seas on Thursday. These two wave trains converging from different directions will produce chaotic oceanographic conditions on the water.

This northwesterly sea and swell will decrease to 6 to 8 feet (with a 14- to 16-second period) Friday into Sunday.

Seawater temperatures

Seawater temperatures will range between 59 and 62 degrees through Wednesday, decreasing to 57 and 60 degrees Thursday, and will remain at this level through Friday.

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At PG&E, your safety is our first concern. This week’s long-period waves could produce strong rip currents along many of our beaches. Please, never turn your back to the ocean, as sneaker waves can inundate beaches and pull people into the water. If you’re caught in a rip current, swim out of the current in a direction following the shoreline. When out of the current, swim at an angle — away from the current — toward shore.

This story was originally published November 29, 2015 at 8:19 PM with the headline "SLO County weather forecast for the week of Nov. 30."