Weather forecast: Significant rain coming to the Central Coast

After an extended period of mostly dry condition in the heart of our rainfall season, the first significant storm of 2022 is expected to reach the Central Coast on Sunday afternoon into Monday.

Moderate to fresh (13 to 24 mph) southerly winds and an approaching storm will allow the marine layer to deepen in the coastal regions on Sunday morning with pockets of fog and heavy drizzle.

Sunday’s high temperatures will reach the mid-60s throughout the Central Coast, cooling to the high-50s on Monday.

A significant change in the weather pattern is forecast to develop on Sunday afternoon into Monday. A 997 millibar low-pressure system and associated cold front strengthen by vigorous upper-level winds will produce moderate gale-force to fresh gale-force (32 to 46 mph with gusts to 55 mph) southerly winds, noticeably cooler temperatures on Sunday afternoon. Moderate to locally heavy rain throughout the Central Coast is forecast to start Sunday night and continue through Monday night.

This storm should produce between 1 and 2 inches of precipitation with up to 3 inches in the Santa Lucia Mountains with snow levels dropping to 6,000 feet. This low-pressure system will rotate into Southern California Monday on Tuesday. Increasing atmospheric instability will produce a chance of thunderstorms Monday afternoon. Remember, when thunder roars go indoors.

Strong to gale-force (25 to 38 mph) northwesterly winds, partly cloudy to mostly clear skies and normal seasonal temperatures are forecast on Tuesday.

A dry cold front will move through the Central Coast on Wednesday morning and will produce a steep pressure gradient along the Central California coastline. Consequently, moderate gale-force to fresh gale-force (32 to 46 mph with gusts to 55 mph) northwesterly winds will develop along the coastline on Wednesday afternoon and continue through Friday. These winds should be strong enough to mix out the marine layer, leaving behind clear skies and below normal seasonal temperatures along the coastline and coastal valleys (San Luis Obispo).

Surf report

Increasing southerly winds will generate a 5- to 7-foot (180-degree, shallow-water) seas on Sunday afternoon and night, followed by a 11- to 13-foot westerly (265-degree, deep-water) swell (with an 8- to 12-second period) on Monday.

A 7- to 9-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 12-second period) is forecast along our coastline on Tuesday through Wednesday, increasing to 8- to 10-feet on Thursday into Friday.

Seawater temperatures will range between 52 and 54 degrees through Tuesday, decreasing to 49 and 51 degrees on Wednesday into Friday with the increased amount of upwelling.

This week’s temperatures

LOWS AND HIGHS, PASO ROBLES

LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS

PG&E safety tip

Stay away from downed power lines. Assume downed power lines are energized and dangerous. Stay away from the lines, and keep others away from them. Call 9-1-1 immediately to report the location of a downed line. After reporting the downed line, call PG&E at 1-800-743-5000.

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 27, 2022 at 5:00 AM.