SLO County weather forecast calls for warm, windy days. Will it rain again?

After Saturday’s rain, the eastern pacific high off the California coastline will keep the storm track well to north. Mostly clear, windy and warmer weather will develop Sunday through Tuesday.

The marine layer will return to the coastal regions on Wednesday through Friday as the winds relax and low pressure develops over the Central Valley of California.

A vigorous late-season, upper-level, low-pressure system moved over the Central Coast with rain on Saturday.

Given the longer daylight hours this time of year, added solar heating may increase atmospheric instability. As a result, thunderstorms accompanied by gusty winds, heavy rain, small hail and lightning strikes are possible.

In this storms wake, on Sunday into Tuesday, a transitory ridge of high pressure will build over eastern California and the eastern pacific high centered about 800 miles to the west of the Central Coast will strengthen to 1,030 millibars.

This condition will produce gentle to moderate (8 to 18 mph) Santa Lucia (northeasterly) winds during the morning, shifting out of the northwest and increasing the strong to gale-force (25 to 38 mph) levels in the afternoon along the shoreline, resulting in mostly clear skies.

Meanwhile, the Central Coast can also expect for areas of overnight and morning fog in the inland and coastal valleys.

Temperatures will warm Monday through Friday to the high 70s to low 80s in the inland valleys (Paso Robles) and low to mid-70s in the coastal valleys (San Luis Obispo).

The beaches will reach the 60s, except for Cayucos, Avila Beach and Shell Beach, which will hit the 70s on Monday and Tuesday.

A trough of low pressure will develop along the California Coastline on Wednesday through Friday. This condition will produce a pattern of gentle variable winds during the overnight and morning, increasing out of the northwest to gentle to moderate (8 to 18 mph) levels later in the morning through the evening.

This condition will create a deep and persistent marine layer along the coastline with overnight and morning dense fog, mist and even drizzle in the coastal regions.

Over the period, most beaches will only see a partial clearing in weather patterns reminiscent of summer.

Further inland, the marine layer will clear later in the morning through the afternoon.

Long-range numerical models suggest a dry weather pattern through the second week of May. However, forecasting springtime precipitation is notoriously tricky — longer days and increased sunshine add instability to the atmosphere, allowing weather patterns to shift rapidly.

Surf Report:

A 5- to 7-foot northwesterly (305-degree deep water) sea and swell (with a 5- to 11- second period) is forecast on Sunday through Tuesday.

A 4- to 6-foot northwesterly (290-degree deep water) swell (with an 8- to 12-second period) is forecast along our coastline on Wednesday, decreasing to 2- to 4-feet (with an 8- to 11-second period) on Thursday into Friday morning.

Increasing northwesterly winds will generate increasing northwesterly sea and swell on Friday afternoon through next week.

Combined with this northwesterly sea and swell will be a 1- to 2-foot Southern Hemisphere (200-degree deep water) swell (with an 18- to 20-second period) on Sunday into Monday, increasing to 2- to 3-feet (with a 15- to 17-second period) Tuesday through Wednesday.

Surface seawater temperatures will range between 51 and 53 degrees through next Saturday.

On this date in weather history (April 27)

1988: Mount Washington, New Hampshire, reported 7 feet of snow over ten days, pushing their snowfall total for the month past the previous record of 89.3 inches set in 1975. (The National Weather Summary)

2016: A late season and relatively cool low-pressure system traveled down the middle of the state and spread increasing clouds and scattered rain showers throughout the Central Coast during the afternoon.

This week’s temperatures

LOWS AND HIGHS, PASO ROBLES

LOWS AND HIGHS, 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 X @PGE_John.

This story was originally published April 27, 2025 at 5:00 AM.