“Our vineyards have never looked as good as they do this year,” the head winemaker of Golan Heights Winery, Victor Schoenfeld, said in a phone call from his winery office in Israel on Sunday. “Isn’t that ironic?” While Katyusha rocket attacks have rained down in the north of the country for the last month, he said the rugged, lightly populated Golan Heights adjoining Syria has been only slightly impacted. “We did have one hit a few hundred yards next to our car wash,” he said. “Luckily, it didn’t explode.”

Our conversation was interrupted at Mr. Schoenfeld’s end by the wail of a siren. “Gotta go to the shelter,” he said. “Actually, where we go is the winery’s underground tasting room.” He recently built a house for his family a half hour’s drive from the winery. “Luckily, I made the bomb shelter extra large, because it also doubles as my wine cellar,” he said.

The advent of harvest is, almost everywhere, suffused with good cheer and camaraderie. But whether that will be the case this season in Israel and Lebanon is an open question. If Monday’s cease-fire holds, it will have come just in time to save the harvest in a region that is both the cradle of viticulture and, increasingly, the source of a new wave of fine wine. If, however, the war flares again, much of the crop will be left to rot on the vine.

The lion’s share of Israel’s best vineyards lie on the Golan Heights to the northeast, and in other higher elevations of the Upper Galilee, closer to Lebanon. Dozens of wineries have sprung up in this area since the early 1990’s, and all are in range of the Katyushas originating in Southern Lebanon. At the Recanati winery in the Hefer Valley, for example, winemaker Lewis Pasco told me that he would usually start harvesting high quality chardonnay at Manara, a kibbutz in the northern Gallilee, around August 20. “It’s been raining rockets up there,” Mr. Pasco said. “The house next to my vineyard manager’s home was flattened by a Katyusha. I’ve tried to go up there a couple of times to check on the vineyards, but the army wouldn’t let me in.” For now, Mr. Pasco, who was a chef before training a winemaker in California, prays for a truce that will hold. “You don’t live in this country unless you’re an optimist,” he says.

One of Israel’s handsomest modern buildings houses the three-year-old Galil Mountain Winery at Kibbutz Yiron, a border settlement in the Upper Galilee. It’s a sleek, low-slung, wood-faced structure that hugs the rolling terrain. At one end is a tasting room with sweeping views of orchards and vineyards, at the foot of a range of hills in Lebanon. The winery, largely deserted since the war began, has been spared damage so far, but Galil Mountain’s vineyards have taken several direct Katushya hits. “One rocket kills about 40 or 50 vines,” the head winemaker, Micha Vaadia, said by phone on Sunday. “It’s the equivalent of about 300 bottles of wine. In the big picture, it’s more an emotional than actual loss, especially to our vineyard manager who sees his vines burnt.”

At the time the war started last month, Galil Mountain’s staff usually would have been gearing up for harvest. But, Mr. Vaadia says, “In the first two weeks, nobody showed up. Now everyone is anxious to come back. I was at the winery earlier today, but the army told me that that it was too dangerous to stay around and I should leave.” Can the harvest go forward? “We were able to do most of our pre-harvest activity in time except for one vineyard, where we didn’t manage to do cluster thinning,” Mr. Vaadia said. “If the ceasefire holds, we’ll be looking good. But if things are going to get harsh again, we won’t be able to harvest this year.”

Less than 50 miles separate Israel’s prime vineyards from those of Lebanon in the Bekaa Valley, a 3,000-foot-high plain between a pair of mountain ranges. The Bekaa is also prime territory for terrorist operations and weapons smuggling operations from Syria which have been targeted by Israeli air and ground strikes in this war. “Happily, we’d already received our new oak barrels before the war started,” Ramzi Ghosn, of the up-and-coming Lebanese winery Massaya, said by phone last Friday. “But we don’t know if we will have the opportunity to harvest. We pick grapes here by hand, and the work is normally done by Kurds, but they are still in Syria and Turkey, waiting to see what happens here. We hope to overcome this problem, if necessary, by using Lebanese students for the harvest. We just need a safe window to do it. And that’s up to the airplanes.”

Israeli aircraft have repeatedly struck the Hezbollah stronghold of Baalbek in the Bekaa Valley, a few miles from Massaya. But Baalbek is known for more than bombing, Mr. Ghozn said. “It’s better known as the home of the largest and oldest and most magnificent temple dedicated to wine on earth.” He is referring to the Temple of Bacchus, a second-century Greek temple, restored early in the 20th century, whose intact grandeur makes it one of the wonders of the classical world. It is also a symbol of this region’s long prominence as a wine source.

“Wine is more than a consumer product,” Mr. Ghozen said. “It is culture. Why can’t we focus on wine instead of war?”