Update 6 p.m.:
The San Luis Obispo County Office of Emergency Services expects Lopez Lake to spill on Wednesday night, the agency said in a Tweet.
As of about 5:45 p.m. on Wednesday, the reservoir was 99% full, according to the SLO County Public Works Department.
The county’s evacuation warning for Oceano residents living near the Arroyo Grande Creek Levee will remain in place on Wednesday night, the SLO County Office of Emergency Services said.
“Lopez has not yet spilled and we want to ensure the water entering the creek will not cause a safety risk near the levee,” the agency said in the Tweet.
The EVACUATION WARNING for Oceano residents near the AG Levee will remain overnight. Lopez has not yet spilled and we want to ensure the water entering the creek will not cause a safety risk near the levee. We are anticipating Lopez will spill tonight. https://t.co/ZkLhQJnoLC
— SLO County OES (@slocountyoes) March 23, 2023
The latest storm to hit San Luis Obispo County brought more than 2 inches of additional rain to the region this week.
Leading the way were the higher elevation areas in the Santa Lucia Mountains near Nacimiento Lake.
Las Tablas south of Nacimiento recorded the highest local total at 2.55 inches over the two days ending at 4 a.m. Wednesday, while Rocky Butte, a peak east of San Simeon with an elevation of 3,245 feet, recorded 2.17 inches.
Santa Margarita recorded 1.78 inches, while Cal Poly totaled 1.18, according to the National Weather Service.
Here are the two-day rainfall total amounts, according to the National Weather Service.
Las Tablas south of Lake Nacimiento: 2.55 inches
Northern Lake Nacimiento area: 2.32 inches
Rocky Butte: 2.17 inches
Santa Margarita: 1.78 inches
Lake Lopez: 1.62 inches
Los Osos: 1.21 inches
West Atascadero foothills: 1.19 inches
Cal Poly: 1.18 inches
Templeton: 1.14 inches
San Luis Obispo: 1.13 inches
Arroyo Grande: 1.12 inches
Davis Peak: 0.95 inches
Paso Robles: 0.91 inches
Carrizo Plain: 0.9 inches
Atascadero: 0.79 inches
Cambria: 0.78 inches
Nipomo: 0.76 inches
Pismo Beach: 0.71 inches
Oceano: 0.71 inches
Shandon: 0.7 inches
Forecast for SLO County
Meanwhile, while the sun started to break through the clouds on Wednesday, more rain was still in the forecast throughout the day, with up to another half inch of rain and wind gusts up to 15 mph expected, the National Weather Service said.
A flood watch was in place for SLO County until 5 p.m.
Lighter showers will continue on Wednesday night, followed by a mostly sunny forecast on Thursday.
Update on Lopez Lake
The extra rain continues to fill Lopez Lake, which could spill for the first time in 25 years.
On Wednesday morning, the lake was at 98.2% capacity, according to the SLO County Public Works Department.
That led the county to extend an evacuation warning for Oceano residents living near the Arroyo Grande Creek Levee, according to the SLO County Emergency Operations Center.
“Heavy rain in combination with spill from the reservoir could result in flooding near the levee,” the agency said in the news release.