A record wet winter plus a record hot summer have meant challenges for local grape growers and winemakers.

Most recently, the heat wave over Labor Day weekend turned some grapes on the region's vines into raisins. That's not good for winemaking.

At the 80th annual Lodi Grape Festival Friday evening, ABC10 chatted with local winemakers about the weather's potential impact on price and availability of wine in the near future.

Tom Hoffman of Heritage Oak Winery is a fifth generation farmer and first generation winemaker. He produces about 2,500 cases of wine per year and about 400 tons of grapes for his and other wineries.

"Most of my vineyards withstood the heatwave very well. They had adequate irrigation," he said.

But he lost 10 acres of Sauvignon Blanc grapes this wet winter.

"You take risks when you farm, so, I mean, I had vineyards that were flooded this winter," he said. "That's farming!"

Bob Lauchland is a winemaker and fourth generation grape grower, meaning he has seen great and terrible growing seasons alike.

"We lost probably 20 percent of the crop due to hail damage, and the leaves got shredded a little bit," he said, describing 2017's conditions. "This was a little difficult. We had a lot of early rains, which means a lot of canopy growth - a lot of green growth. And then we had some heat, late-late, that's made it difficult. We've got to keep our workers safe and then trying to get the fruit in, in a healthy condition."

Another challenge facing grape growers right now is an increasing shortage of laborers to harvest the fruit.

"How bad is it going to get?" Lauchland asked. "We need to develop some sort of Bracero Program or a way to bring workers legally into this country, who want to work and can meet all the legal requirements of working here."

On Friday morning, he said, only about a quarter of the workers he needed and expected turned out to pick grapes, so he had to tell the winery for which he was delivering that the full load of fruit would be delayed, as a result.

"There are other opportunities for some of the workers in California, but also there's just less workers, for whatever reason, than there have been in the past," he said.

So will all these challenges be enough to prompt a rise in the price of wine anytime soon?

These winemakers say, probably not.

"I doubt it," said Hoffman.

"We've got a good supply of good California wines, and Lodi's featuring stuff that's very affordable and a good value for everybody," said Lauchland. "I think consumers will be pleased with what we have this year."

ABC10 meteorologist Harry Stockman explained the weather's impact on grapes.

"Grapes are sensitive to the weather: heat, cold and rainfall, and this summer we had record warmth," Stockman said. "This last heatwave got up to 110 degrees...And so the plant needs to survive, and it takes water from the fruit, and that can turn the fruit into a raisin. So the heat, at the wrong time, is a big problem for the grape growers."

Now, Hoffman said, he's concerned about cooler weather forecasted this month, "because we need heat to get the fruit ripe."

75-degree days aren't great, he said. Ideally, the grapes would get 90-degree days and cool nights.

"You need heat, but you don't want all the heat at once," Hoffman explained.

Grape harvest in Northern California typically spans mid-August through early to mid-October.