Here is this week’s weather forecast from PG&E meteorologist John Lindsey.
This morning’s deep marine layer will produce a few pockets of mist and drizzle along the beaches and coastal valleys. The cloud cover is expected to gradually burn off into the early afternoon, giving way to variably cloudy skies as monsoonal moisture continues to drift over the Central Coast from the south.
As a result, today’s maximum temperatures will be cooler across San Luis Obispo County, especially in the North County. Maximum temperatures on the eastern side of the Cuesta Grade will reach the mid-80s. The coastal valleys will reach the mid-70s, while the beaches will remain in the 60s.
As the subtropical moisture continues to interact with an upper-level low-pressure system near San Diego, thunderstorms are expected to develop along the Sierra, with a slight chance for some stray showers to drift across lower elevations. The threat of lightning could spark fires and will need to be closely monitored.
Across San Luis Obispo County, monsoonal moisture will produce mild overnight temperatures and muggy conditions.
A gradual warming trend is forecast to start Wednesday and continue into the weekend, with temperatures warming to above-normal across the North County and near-normal along the coast.
The thunderstorm threat decreases Thursday and remains low through the weekend as monsoonal moisture moves off to the east.
PG&E safety tip: “When thunder roars, go indoors.” The U.S. reports an average of 51 fatalities a year by lightning strikes.
Today’s surf report
Arriving from the northwest: Today’s 2- to 4-foot northwesterly (310-degree, deep-water) swell (with a 7- to 9-second period) will remain at this height and period through Wednesday, increasing to 3 to 5 feet with the same period Thursday into Sunday.
Arriving from the south: A 1- to 3-foot southerly (185-degree, deep-water) swell (with an 11- to 13-second period) from Hurricane Iselle will arrive along our coastline today and will remain at this level through Tuesday.
A 1- to 2-foot Southern Hemisphere (190-degree, deep-water) swell (with an 18- to 20-second period) will arrive along our coastline Wednesday and remain at this level but with a gradually shorter period through Saturday.
Seawater temperatures are forecast to range from 59 to 64 degrees through Saturday.