Weather Watch

SLO County weather forecast for the week of July 27

Low 80s along the coast and triple digits inland for this week.
Low 80s along the coast and triple digits inland for this week.

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

Monday morning’s coastal low clouds with areas of mist are expected to clear from the coastal valleys and beaches by Monday afternoon.

Monday’s maximum temperatures at the Mid-State Fair will reach the mid-90s, while temperatures in the coastal valleys will hit the low 80s. High temperatures along the beaches will range from the mid-60s along the northwesterly facing beaches of Morro Bay, Los Osos, Montaña de Oro and Nipomo, to the high 60s along the westerly facing beaches of Cambria, Grover Beach and Pismo Beach. The southwesterly facing beaches of Cayucos and Avila Beach will reach the low 70s.

High pressure is expected to build over the Central Coast from the desert Southwest on Tuesday into Thursday. This condition will result in decreasing northwesterly (onshore) winds and warmer temperatures, especially at the Mid-State Fair. High temperatures at the fair will reach 103 degrees Tuesday and 105 Wednesday. Temperatures in the coastal valleys will range from the low to mid-80s. Temperatures along the beaches will be quite a bit cooler, mostly in the 60s, with only partial afternoon clearing of the marine layer.

The northwesterly (onshore) winds will increase Friday into Sunday for cooler temperatures and a deeper marine layer that will produce fog and areas of drizzle. There will also be some subtropical moisture and clouds moving northward into the region toward the end of the week. This monsoonal moisture will produce a chance for rain showers or thunderstorms in the Sierra Nevada.

Monday’s surf report

Increasing northwesterly winds off the coast will generate a 5- to 7-foot northwesterly (315-degree, deep-water) sea and swell (with 5- to 11-second period) through Monday night, decreasing to 4 to 6 feet with the same period Tuesday. Rough, indeed!

A 3- to 5-foot northwesterly (300-degree, deep-water) swell (with an 8- to 10-second period) will develop along our coast Wednesday and will remain at this height and period through Friday morning. Increasing northwesterly winds will generate a 3- to 5-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- to 9-second period) Friday afternoon into Sunday.

Arriving from the Southern Hemisphere Monday’s 1- to 2-foot Southern Hemisphere (210-degree, deep-water) swell (with a 16- to 18-second period) will build to 2 to 3 feet (with a 15- to 17-second period) on Tuesday into Thursday, decreasing Friday.

Seawater temperatures

Abnormally warm seawater temperatures will continue for an extended period. Temperatures will range between 56 and 62 degrees through Tuesday, increasing to 58 and 64 degrees Wednesday into Friday.