Weather Watch

SLO County weather forecast for the week of Oct. 20

Here is this week’s weather forecast by PG&E meteorologist John Lindsey.

A weak cold front is expected to produce increasing clouds with a few pockets of mist and drizzle in the coastal regions this morning. Partly cloudy conditions are expected this afternoon, with maximum temperatures in the low to high 70s in the North County and coastal valleys. High temperatures along the beaches will reach the 60s.

A pattern of moderate to fresh (13- to 24-mph) Santa Lucia (offshore) winds developing during the night and morning, shifting out of the northwest and increasing to strong to gale-force (25- to 38-mph) levels during the afternoon along the coastline, will start Tuesday and continue through Thursday. This pattern will produce clear skies and warmer temperatures, especially in the coastal regions, through Thursday.

A persistent and strong onshore flow starting Friday and continuing through Sunday will allow for night and morning marine low clouds to develop along the coast and coastal valleys. A series of weather systems will move into Northern California through next week, producing rain north of the Golden Gate. However, San Luis Obispo County will remain dry.

Today’s surf report

A 975-millibar storm developed in the Gulf of Alaska on Sunday. An 8- to 10-foot northwesterly (300-degree, deep-water) swell (with an 18- to 20-second period) from this storm will arrive along the county’s coastline late this morning into tonight. Strong to gale-force (25- to 38-mph) northwesterly winds along the California coast will further build this northwesterly sea and swell to 9- to 11-feet (with a 5- to 17-second period) Tuesday.

This northwesterly sea and swell will decrease to 6- to 8-feet (with a 6- to 13-second period) Wednesday and will remain at this level through Saturday.

An 8- to 10-foot northwesterly (305-degree, deep-water) sea and swell will arrive along our coastline Sunday into next Monday.

Hurricane Ana off the Hawaiian Islands has the potential to turn extratropical as it moves toward the Gulf of Alaska and could rapidly intensify next week.  

Seawater temperatures

A large and deep body of relatively warm seawater has moved from the south and is extending along the Central Coast northward toward Point Reyes. Seawater temperatures will range from 63 to 67 degrees through tonight. Increasing northwesterly winds will produce a seawater cooling trend starting Tuesday and continuing through the weekend.

PG&E safety tip

If you are observing the high waves along the coastline, please remember to never turn your back on the ocean.