A 1,028-millibar Eastern Pacific High about 550 miles northwest of San Luis Obispo combined with a 1,026-millibar high over the Great Basin will produce northeasterly (Santa Lucia) winds this morning. These Santa Lucia winds will produce clear skies along the beaches and along the coastal valleys. However, areas of fog may develop in the North County but will clear later this morning. Today’s maximum temperatures will reach the high 60s across San Luis Obispo County. Minimum temperatures will remain above the freezing level.
The ridge of high pressure will begin to break down later tonight allowing for increasing northwesterly winds, cooler temperatures and partly cloudy skies Tuesday through Thursday.
An area of low pressure will drop out of the Gulf of Alaska and move toward the Central Coast on Thursday night. Rain showers will cross San Luis Obispo County on Friday. The primary uncertainty with the forecast is the amount of moisture associated with the system, which will dictate how much precipitation is produced. At this time, rainfall amounts will be light with only about a quarter of an inch expected. Snow levels will fall rapidly down to near 2,500 feet as this system moves through. However, only a few inches of snow will fall.
The main effect of this system will be to produce moderate gale-to-fresh-gale (32- to 46-mph) northwesterly winds along the coastline and cool conditions. In fact, maximum temperatures will only reach the 50s.
Dry conditions will return Saturday and will persist through the entire following week as high pressure dominates our weather.
This morning’s 5- to 7-foot northwesterly (300-degree deep-water) sea and swell (with a 5- to 14-second period) will gradually decrease to 3 to 5 feet Tuesday.
A 9- to 11-foot northwesterly (310-degree deep-water) sea and swell (with a 7- to 17-second period) will arrive along our coastline Wednesday and will remain at this height but with a gradually shorter period through Saturday.
A 5- to 7-foot northwesterly (310-degree deep-water) swell (with an 18- to 20-second period) will arrive next Sunday, peaking next Monday at 8 to 10 feet (with a 15- to 17-second period).
Seawater temperatures will range between 52 and 54 degrees through Saturday.
Weekly Forecast is written by John Lindsey and is special to The Tribune. Lindsey is a PG&E meteorologist whose Weather Watch column appears in the Local section on Sundays.