SLO County weather forecast for week of Jan. 24: Rain, gale-force winds on the way

After weeks of dry and warm winter weather, a significant change in the weather pattern is underway as the Eastern Pacific High moves 2,000 miles to the west of California, opening the door to a series of storms that will bring much-needed rain and snow to the Golden State this week. Unfortunately, these storms will also produce gale-force winds, so strap into your seat and batten down the hatches; it’s going to be a rough ride.

Sunday will start clear, calm, and cold, then clouds will increase Sunday afternoon, with rain developing Sunday evening and night as a cold front moves southeastward through the Central Coast. A 1,040 millibar high well off the Oregon coastline will produce a steep pressure behind this cold front. Consequently, moderate gale-force to fresh gale-force (32 to 46 mph) northwesterly winds with gusts of 60 mph along the coastline and a few scattered rain showers is forecast on Monday. Total rainfall amounts with this system should range between 0.10 and 0.33 of an inch. Snow levels could lower to 2,000 feet.

A break in the weather will develop on Tuesday with partly cloudy skies and decreasing winds.

A 988 millibar storm will develop off the far Northern California coastline. The associated and intense cold front to the south will tap subtropical moisture and take on the characteristics of an Atmospheric River (AR) as it moves slowly southeastward through the Central Coast.

This storm will produce fresh gale-force to whole gale-force (47 to 63 mph) southerly winds with gusts to 70 mph along our coastline and periods of moderate to heavy rain on Wednesday through Thursday. NOAA’s Global Forecast System (GFS) model indicates that this cold front could stall over the Central Coast. Simultaneously, the European Center for Medium-Range Weather Forecast shows the front stalling over the LA basin. At this time, between 2 and 4 inches of rain is expected along the Central Coast; however, if the front stalls over a particular area, rainfall amounts will be much higher.

A few rain showers and decreasing winds are forecast on Friday and Saturday. Additional wet weather is possible next week, but current estimates show much less rain than this midweek system; details will be provided as the forecast evolves in the coming days.

The National Weather Service has issued a Gale Watch which begins Sunday at 9 p.m. until Tuesday at 9 p.m. A Small Craft Advisory began Saturday morning lasting until Sunday at 9 p.m. The affected area is from Point Piedras Blancas to Point Sal westward out to 10 nautical miles.

Surf report

An 8- to 10-foot northwesterly (305-degree, deep-water) sea and swell (with a 7- to 22-second period) is forecast along our coastline on Sunday.

Moderate gale-force to fresh gale-force (32 to 46 mph) northwesterly winds along our coastline will produce a 13- to 15-foot northwesterly (320-degree, deep-water) sea and swell (with a 6- to 18-second period) on Monday, decreasing to 10 to 12 feet on Tuesday.

Seawater temperatures will range between 54- and 56-degrees through Sunday, decreasing to 50- to 52-degrees on Monday into Tuesday. Seawater temperatures will rise on Wednesday through Saturday.

Fresh gale-force to whole gale-force (47 to 63 mph) southerly winds will generate a 13- to 15-foot southerly (200-degree, deep-water) sea and swell (with a 5- to 11-second period) on Wednesday, building to 16 to 18 feet (with a 5- to 16-second period) on Thursday.

An 8- to 10-foot west-northwesterly (290-degree, deep-water) swell (with an 8- to 14-second period) is forecast along our coastline on Friday, decreasing to 4 to 6 feet by Saturday.

This week’s temperatures

LOWS AND HIGHS, PASO ROBLES

LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS

PG&E safety tip

PG&E Safety Message: This week’s storms may produce power outages. To prepare for storms, please visit www.pge.com for preparedness tips.

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 January 24, 2021 at 5:00 AM.