SLO County braces for more big waves after overnight storm brings rain, flood warning
San Luis Obispo County braced for another day of big waves and pounding surf on Saturday after an overnight storm brought more than an inch of rain to most areas.
San Luis Obispo received 1.67 inches of rain, while 1.6 inches fell in Arroyo Grande, 1.43 fell in Cambria and 0.9 fell in Templeton. Rocky Butte received the highest 24-hour total at 2.56 inches.
The National Weather Service issued a flood advisory advisory late Friday night due to heavy rainfall across the Central Coast.
The Weather Service said Doppler radar indicated heavy rain “due to moderate to locally heavy rainfall,” at 11:32 p.m. with rainfall rates between 0.25 and 0.50 inch per hour, which could cause minor flooding in low-lying and poor drainage areas.
The heavy rain washed out part of Halcyon Road leading to the Nipomo Mesa, according to the California Highway Patrol.
Halcyon Road Closed in both directions to through traffic just north of SR-1 (Upper Halcyon), road washed out on Southbound side. #CHP #RoadClosure pic.twitter.com/HbTudGEuy3
— CHP San Luis Obispo (@ChpSlo) December 30, 2023
The road, which is typically an alternative to Highway 1, was closed by CHP after a citizen made a report to CHP at 6:49 a.m. Saturday morning.
Travelers were advised to avoid the road until further notice.
Avila Beach was closed due to flooding on 1st Street and San Francisco Street, according to a post from the San Luis Obispo County Public Work’s X — formerly Twitter — account.
1st Street at San Francisco in Avila Beach is closed because of local flooding. High tides and large surf are backing up San Luis Creek, which prevents the area from draining. Expect flooding to recede on low tides after large surf ends. pic.twitter.com/emT9lCW8h3
— County of SLO Public Works (@SLOCountyPWD) December 30, 2023
More big waves coming to SLO County
Meanwhile, the Weather Service issued a high surf warning for San Luis Obispo and Santa Barbara counties through 10 p.m. Saturday.
Powerful cyclones in the Pacific Ocean cause the high swells, which create “extremely dangerous conditions” on the beaches, according to the Weather Service’s forecast discussion.
Breaking waves on the Central Coast will continue to be 10 to 15 feet tall with the potential for 25 feet, the Weather Service said.
“These are forecast to be extremely dangerous conditions, as powerful waves and life-threatening rip currents pose an exceptional risk of ocean drowning and damage to coastal structures such as piers and jetties,” the Weather Service wrote in Friday’s forecast discussion.
The Weather Service also issued a coastal flood warning for the San Luis Obispo County coast through Saturday evening — especially in low-lying coastal areas around the morning high tides.
In its daily forecast, the Weather Service said astronomical tides are “running a few to several tenths of a foot above normal,” and high tide will range from 5.7 feet to 6.5 feet.
That, coupled with the tides being at the peak of their monthly maximum, increased the risk of coastal flooding, the agency said.
“Overall, this is expected to be an exceptional high-surf and coastal flooding event that has not occurred in many years,” the Weather Service said. “Take caution and heed the direction of local authorities and lifeguards.”
Rain totals across SLO County
Here’s a look at how much rain fell over the last 24 hours:
Rocky Butte: 2.56 inches
South Portal: 1.54 inches
Atascadero: 0.63 inches
Lopez Dam: 1.36 inches
Santa Margarita: 1.15 inches
Nipomo East: 1.76 inches
San Luis Obispo off Broad Street and Industrial Way: 1.67 inches
San Luis Obispo Reservoir: 1.5 inches
Arroyo Grande: 1.59 inches
Davis Peak: 1.42 inches
Cambria: 1.43 inches
Templeton: 0.9 inches
San Simeon: 1.01 inches
Los Osos: 1.26 inches
Nipomo South: 1.41 inches
Oceano: 1.88 inches
Canet near Morro Bay: 1.54 inches
Shandon: 0.71 inches