SLO County weather: Light rain showers and cold front ahead
A storm from the north created rain showers on Saturday. Dry weather will develop on Sunday into Monday before a fast-moving cold front generates a few light rain showers on Tuesday. Northwesterly gales and freezing temperatures are expected in the cold front’s wake. Dry weather is forecast for Wednesday through Thursday, with another chance of rain on Friday.
Gusty Santa Lucia (northeasterly) winds on Sunday morning will produce clear to partly cloudy skies, followed by fresh to strong (19 to 31 mph) northwesterly (onshore) winds during the afternoon. This onshore flow will allow the marine layer to develop along the coastline by Sunday evening and move inland Sunday night.
Gentle to moderate (8 to 18 mph) Santa Lucia (northeasterly) winds on Monday morning should produce some clearing; however, the winds will shift out of the northwest and allow a few areas of low marine clouds to develop along the coastline.
A rapidly moving cold front will travel southward over the state of California and will produce a few scattered light rain showers, with snow levels dropping to 2,500 feet on Tuesday. The main impact of this low-pressure system will be to create a steep pressure gradient along the California coastline that will generate moderate gale-force to fresh gale-force (32 to 46 mph with gusts to 50 mph) northwesterly winds on Tuesday. Highs on Tuesday and Wednesday will only reach the mid-50s, with the winds making it feel much colder.
Northerly upper-level winds (Jet Stream) from Canada 150 mph and higher will flow over much of California and will bring a chilly air mass to the state, with lows lowering to the high-20s in the inland valleys (Paso Robles) and low-30s in the coastal valleys (San Luis Obispo) on Wednesday morning with widespread frost.
The winds will decrease to fresh to strong (19 to 31 mph) levels on Wednesday afternoon and night, allowing areas of low marine clouds to develop along the coastline.
Moderate to fresh (13 to 24 mph with gusts to 35 mph) Santa Lucia (northeasterly) winds during the night and morning on Thursday will create clear skies.
The next chance of increasing southerly winds and rain is expected on Friday.
Surf report
A 9- to 11-foot northwesterly (290-degree, deep-water) swell (with an 8- to 15-second period) is expected along our coastline on Saturday through Sunday morning, decreasing to 5- to 7-feet (with an 8- to 20-second period) Sunday afternoon through Monday morning.
Increasing northwesterly winds off the California coastline will generate a 10- to 12-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 17-second period) on Monday afternoon and night, peaking on Tuesday at 14- to 16-feet (with a 5- to 15-second period). This northwesterly sea and swell will decrease to 9 to 11 feet (with a 7- to 14-second period) on Wednesday.
A 4- to 6-foot northwesterly swell (with an 8- to 20-second period) will arrive along our coastline on Thursday and will remain at this level through Friday.
Seawater temperatures will range between 57 and 59 degrees through Monday, decreasing to 50 to 53 degrees on Tuesday and will remain at this level through Friday.
This week’s temperatures
LOWS AND HIGHS, PASO ROBLES
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
33, 62 | 35, 63 | 36, 52 | 28, 53 | 27, 58 | 37, 55 | 37, 59 | 39, 61 |
LOWS AND HIGHS, SAN LUIS OBISPO AND COASTAL VALLEYS
SUN | MON | TUE | WED | THU | FRI | SAT | SUN |
42, 63 | 42, 63 | 41, 55 | 33, 56 | 34, 59 | 44, 58 | 42, 62 | 49, 65 |
John Lindsey is a retired PG&E marine meteorologist. Email him at JohnLindseyLosOsos@gmail.com or follow him on Twitter @PGE_John.