Weather Watch

SLO County weather forecast for the week of May 19

Weather report

This morning’s marine low clouds will clear as strong to gale force (25- to 38-mph) northwesterly (onshore) winds develop along the coastline. These winds will produce mild temperatures and sunny skies throughout San Luis Obispo County this afternoon.

An upper-level low pressure (551-dm) system will drop out of the Pacific Northwest and slide across Central California on Tuesday into Wednesday. This system will give below-average temperatures and plenty of marine low clouds, fog and drizzle during the night and morning hours.

The system will also produce cumulus clouds along with a chance rain showers and afternoon thunderstorms over eastern San Luis Obispo County. The system will give showers and afternoon thundershowers over much of the Sierra Nevada. 

Temperatures then warm sharply Thursday as high pressure will build across the Central Coast in the wake of the departing low. Warmer conditions then continue Friday and persist through the weekend, when temperatures are expected to return to above-normal; however, no major heat is anticipated at this time.

Surf report

Strong to gale force (25- to 38-mph) northwesterly winds will generate a 4- to 6-foot northwesterly (320-degree, shallow-water) seas (with a 4- to 7-second period) today through Tuesday. 

A 5- to 7-foot northwesterly (300-degree, deep-water) sea and swell (with a 5- to 9-second period) will develop along our coastline Wednesday, decreasing to 4 to 6 feet with the same period Thursday through Friday.  

A 1- to 2-foot Southern Hemisphere (220-degree, deep-water) swell (with a 15- to 17-second period) will arrive along our coastline today into Tuesday. 

A 1-foot Southern Hemisphere (220-degree, deep-water) swell (with a 19- to 21-second period) will arrive Thursday, building to 1 to 3 feet (with a 16- to 18-second period) on Friday through Saturday.

Seawater temperatures

Seawater temperatures will range from 49 to 52 degrees through Tuesday, increasing to 50 and 53 degrees Wednesday through Friday.