SLO County Weather forecast: Scattered rain showers and cooler temperatures
The Santa Lucia (northeasterly and offshore) winds produced dry and clear conditions last week, but a change in the weather pattern will develop Sunday as a low-pressure system will produce increasing clouds, scattered rain showers, and cooler temperatures. Dry weather will follow on Monday through Wednesday.
The winds will turn out of the northwest (onshore), allowing the marine layer to develop along the coastline on Saturday evening and move inland Saturday night into Sunday morning with pockets of mist and drizzle.
A 1,011 millibar low-pressure system over Northern California will move southward through the Central Coast late Sunday morning into Sunday night with mostly cloudy skies, fresh to strong (19 to 31 mph) northwesterly winds, scattered rain showers, and cooler temperatures. In fact, snow levels will drop to 2,500 feet by Sunday night with high temperatures only reaching the low to mid-50s on Sunday and Monday.
Since this storm will be coming from the land versus the ocean, it will be starved for moisture; consequently, rainfall amounts will be light. A 543-decameter upper-level low-pressure system will develop over the Southern California Bight and continue to create widely scattered rain showers into early Monday morning. Total rainfall amounts from Sunday through early Monday morning are forecast to range between a tenth and one-third of an inch.
The skies will clear on Monday afternoon and night.
Moderate to fresh (13 to 24 mph) Santa Lucia (northeasterly) winds during the night and morning, starting later Monday and continuing through Wednesday, will create clear skies and cold mornings. Overnight lows will drop to the high-20s in the inland valleys (Paso Robles) and the mid-30s in the coastal valleys (San Luis Obispo), while daytime highs will only reach the high-50s to the low-60s.
A Pacific storm will generate strong to gale-force (25 to 38 mph) southerly winds and gentle to moderate rain on Thursday afternoon into Friday morning. Total rainfall amounts are expected to range between 0.75 and 1.25 inches with higher amounts in the Santa Lucia mountains. The next chance for rain will occur on the Feb. 8 and Feb. 9.
Surf report
A 6- to 8-foot west-northwesterly (285-degree, deep-water) swell (with an 8- to 16-second period) is expected along our coastline on Sunday morning, decreasing to 5- to 7-feet (with an 8- to 15-second period) Sunday afternoon through Monday.
A 4- to 6-foot northwesterly swell (with an 8- to 17-second period) will arrive along our coastline on Tuesday and will remain at this height but with a gradually shorter period through Wednesday.
Increasing southerly winds on Thursday into Friday morning will generate a 6- to 8-foot (190-degree, deep-water) sea and swell (with a 5- to 15-second period) on Thursday night into Friday.
Seawater temperatures will range between 57 and 59 degrees through Friday.
This week’s temperatures
LOWS AND HIGHS, PASO ROBLES
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
38, 50 | 36, 52 | 28, 56 | 29, 58 | 39, 58 | 40, 60 | 37, 61 | 37, 63 |
LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
43, 53 | 38, 55 | 36, 59 | 37, 60 | 44, 59 | 45, 63 | 42, 64 | 41, 65 |
John Lindsey is a retired PG&E marine meteorologist. Email him at JohnLindseyLosOsos@gmail.com or follow him on Twitter @PGE_John.