Janet Folk is buoyant about the prospect of a wetter-than-average winter coming to the parched North Coast.

The Lake Sonoma marina manager said increased rain during an expected El Niño year could lift water levels and bring more boaters.

Currently, the lake is down about 18 feet, enough to expose submerged trees left behind when the reservoir was made, creating navigation hazards for some larger vessels.

“It would make a huge difference,” said Folk, who noted the lake is still at more than 80 percent of capacity. “A lot of people aren’t using their boats because they are afraid of low water.”

Forecasters say it is likely California will get significant rain this fall as the cyclical weather phenomenon builds in the Pacific Ocean. The Los Angeles Times reported Saturday that scientists say a significant El Niño is more than 90 percent likely.

The tropical weather pattern is created by warmer-than-usual ocean waters that can precipitate thunderstorms.

Warren Blier, National Weather Service science officer, said El Niño could increase precipitation by as much as a third, filling reservoirs and bringing needed snow to the Sierra.

Blier said computer models show it strengthening, increasing the chance of storms starting around Oct. 1.

He predicted Santa Rosa could experience a similar winter to the last El Niño in 1997-1998, when 42 inches of rain fell. This year, Santa Rosa has gotten about 70 percent of its normal rainfall, or just under 25 inches.

However, he said El Niño is not likely to erase four years of drought and could dissipate as time goes on.

“All we can say is it’s looking like the odds of it being wetter-than-average winter are going up,” Blier said.

North Coast residents welcomed the positive though speculative news.

Deanna Tubbs, co-owner of Prickett’s Nursery and Garden Center in Santa Rosa and Healdsburg, hoped it would ease water restrictions that have cut down on gardening.

She said people this summer have scaled back on flowers and vegetable garden planting. More rain could mean a return of more varieties. People contemplating removing their lawns might change their minds, she said.

“I hope it’s true,” Tubbs said. “I guess I’ll believe it when I see it.”

At Lake Sonoma, Folk said water levels are improved over last year, when it was too low to launch power boats at the marina. Rains at the beginning of the year helped fix that, but there’s still an impression that water is scarce, she said.

The Army Corps of Engineers this month closed three of 13 boat-in campgrounds at the lake, saying diminishing water levels make the beach approaches unsafe.

“The drought has kept people away,” Folk said. “I get calls from people wanting to know if they can still put canoes in the water.”

You can reach Staff Writer Paul Payne at 568-5312 or paul.payne@pressdemocrat.com. On Twitter @ppayne.