Storm runoff in Montecito Creek.
Montecito Creek had a healthy flow Monday after a day or heavy rainfall. Montecito received 1.56 inches of rain, but some foothill and mountain areas were douse by more than 5 inches. (Peter Hartmann / Noozhawk photo)

A flood advisory was issued Sunday afternoon for Santa Barbara County, as a strong late-season storm was moving through the region.

Rainfall rates through the afternoon generally ranged between 0.25 and 0.33 inches per hour, according to the National Weather Service in Oxnard, although some areas have seen as much as 0.65 inches per hour.

“Rainfall rates are expected to peak this evening, when there will also be a slight chance of thunderstorms,” the advisory said.

“During this time, rainfall rates between 0.50 and 0.75 inches per hour will become more common across south- and southwest-facing slopes, especially the Santa Ynez range and near thunderstorms.”

Forecasters were expecting widespread roadway flooding from the storm through the evening hours.

“There will also be the threat of rock and mudslides, especially on canyon and mountain roadways,” the advisory said. “The Cave Fire burn area could also see localized and shallow mud and debris flows this evening.”

The advisory originally was to be in effect until 10:45 p.m. Sunday, but it was extended to 4:30 a.m. Monday.

Rainfall totals through Tuesday are expected to range from 1 to 2 inches in coastal and valley areas, and up to 3 inches in the foothills and mountains.

Local rainfall totals to 4 inches or more will be possible in some mountain areas, according to the National Weather Service forecast discussion for Santa Barbara County.

The Santa Ynez River above Lake Cachuma.

The Santa Ynez River was rising Monday, sending water into Lake Cachuma. (Tom Fayram photo)

As of 9 a.m. Monday, Refugio Pass along the Gaviota Coast had received 5.67 inches from the storm, followed closely by San Marcos Pass at 5.56 inches, Tecolote Canyon west of Goleta with 4.90 inches, and the KTYD tower off Gibraltar Road above Santa Barbara with 4.64 inches.

Rancho San Julian southwest of Buellton received at 4.75 inches, and Celite near Lompoc had 3.09 inches.

Other readings included 1.59 inches in Santa Barbara, 1.78 inches in Goleta, 1.56 inches in Montecito, 0.79 inches in Santa Maria, 1.60 inches in Lompoc, and 1.95 inches in Santa Ynez.

The Santa Barbara Airport set a rainfall record for April 5 on Sunday with 1.12 inches. That broke a mark of 0.95 inches set in 1969.

The Santa Ynez River above Lake Cachuma was rising, which should increase the lake level over the coming days and weeks. The lake was at 75% of capacity Monday morning, 17 feet below spill level.

The storm also boosted the countywide seasonal rainfall total to date to 90% of normal.

A chance of showers remains in the forecast through Thursday, with sunny skies returning Friday and through next weekend.

Daytime high temperatures should be around 60, with overnight lows in the mid-40s.

Winds with gusts to 25 mph were in the forecast overnight Sunday into Monday.

» Click here for the latest Santa Barbara area forecast from the National Weather Service.

» Click here for Santa Barbara County real-time rainfall totals.

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Noozhawk executive editor Tom Bolton can be reached at Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.

San Ysidro Creek with a healthy flow after overnight rainfall.

San Ysidro Creek with a healthy flow after overnight rainfall. (Diego Topete / Noozhawk photo)