March storm scenes: Flooding in Avila Beach, Morro Bay
The first significant rain in San Luis Obispo County since the spring is forecast this week.
But first, Monday will be dry with increasing clouds. Then a 1,001 millibar surface low and an associated warm and cold front will gradually move into the Central Coast on Tuesday into Wednesday with moderate to fresh (13 to 24 mph) southerly winds and early-season rain.
Rainfall amounts are forecast to range between 0.25 and 0.75 of an inch. At this time, models continue to struggle with the trajectory, especially with the remnants of Hurricane Rosa factored in, but confidence is growing that there will be rain across the Central Coast.
In fact, rain showers may last into Thursday. A pattern of moderate to fresh (13 to 24 mph) Santa Lucia winds developing during the night and morning hours, followed by fresh strong (19 to 31 mph) northwesterly winds will produce dry and warmer weather Friday through the first weekend of October.
A southerly (165-degree, deep-water) swell from Hurricane Rosa is expected to arrive along the Central Coast on Sunday at 3 to 4 feet (with a 15- to 17-second period), building to 3 to 5 feet (with a 14- to 16-second period) Monday into Tuesday. Note: This swell will be much higher along the Southerly California coast.
A 3- to 5-foot northwesterly (310-degree, deep-water) swell (with a 5- to 10-second period) is forecast along our coastline Wednesday, increasing to 4 to 6 feet (with a 5- to 15-second period) Thursday into next Friday. Several tropical cyclones in the north Pacific could become extratropical as they travel northward and become intense mid-latitude storms. Higher-energy westerly swell from these storms could arrive along our coastline between Oct. 9-11.
Seawater temperatures will range between 56 and 59 degrees through Sunday, warming to 58 to 62 degrees Monday into Wednesday.
This week’s temperatures
LOWS AND HIGHS, PASO ROBLES
LOWS AND HIGHS, SLO AND COASTAL VALLEYS
John Lindsey’s column is special to The Tribune. He is PG&E’s Diablo Canyon marine meteorologist and a media relations representative. Email him at email@example.com or follow him on Twitter: @PGE_John.