Perfection is not a word that usually applies to Bordeaux vintages, but it did sum up 2005. Famously prone to brutalizing hail and pillaging thunderstorms, the world’s most important wine region enjoyed almost spookily perfect conditions in 2005. And then came downright scary prices: $11,000 a case for the Chateau Latour and other First Growths, $3,000 a bottle for Chateau Petrus, a tiny production Pomerol. Vintage 2005 thrashed all previous price records — and it’s a wine that won’t even be delivered until autumn 2008 and won’t reach peak drinkability until at least a decade after that.

Now it’s time for Bordeaux lovers to pop the next big question: Whither vintage 2006? As if to reassert its unpredictability, Bordeaux saw wild swings in weather in the 2006 growing season. July was the hottest in 85 years, while August was the coolest in 20. Then September was the hottest in 60 years. Coining a term of which the protectors of the French language would disapprove, the Bordeaux growers syndicate calls the 2006 weather “climatologie yo-yo.” To cap off the vintage, a mini-tornado swirled through some Medoc vineyards on October 2. Before global warming, as manifested in Bordeaux, that tempest would have pummeled the late ripening cabernet sauvignon vines still laden with fruit. But nowadays, the harvest that once often stretched well into October is now completed weeks earlier. Most châteaux had already completed their harvests by the time the nasty weather hit.

How to sum up 2006? The red wines, now undergoing secondary fermentation, are still unformed. They won’t be tasted until next April, when the trade and journalists descend on Bordeaux to check out barrel samples. To get some advance comments, I headed up to Zachys in Scarsdale last Saturday afternoon, where a group of young Bordeaux winemakers were pouring samples of their recent vintages. Unlike the pervasively perfect 2005, this year’s vintage is likely to be a mixed bag, or what the manager of Chateau Haut-Bailly in Pessac-Leognan, Veronique Sanders, politely calls “a very heterogeneous vintage.” Anabelle Bardinet, a Catherine Deneuve look-alike who is winemaker at Chateau Corbin in St. Emilion, pondered a moment between pouring samples before referring to 2006, with equal tact, as “a connoisseur’s vintage.” Translation: Unlike the 2005 reds, which can be bought blind, 2006 Bordeaux will require demanding buyers to be picky. That said, the best wines should not need to remain in the shadow of the previous vintage. “Our cabernet sauvignon may be superior in 2006 to 2005,” Ms. Bardinet’s cousin and the manager of Chateau d’Issan in Margaux, Emanuel Cruse, said. Told of Mr. Cruse’s verdict, the winemaker at the underrated Chateau Fonbadet in Pauillac, Pascale Peyronie, nodded vigorously. “Exactly,” she said. “My cabernet has more elegance in 2006.”

More than a decade ago, Bordeaux winemakers announced that advances in vineyard and winery techniques spelled the end of bad vintages. I was a doubter. It seemed inevitable that nasty weather would launch new attacks on Bordeaux and, mocking the new technologies, remind us of just how meager the region’s wines can be. But that hasn’t come to pass. Amazingly, there has not been a washout vintage in Bordeaux since 1992. And it’s been a far cry from the 1960s and 1970s: Both decades suffered four bad vintages out of 10. Yes, better techniques have helped. But global warming is Bordeaux’s true savior. More sunny days bring more grape-ripening heat. Recent vintages, too, have seen rainfall deficits, which help to concentrate flavor in the grapes. “It rained during my first harvest at Chateau Corbin in 1999,” Ms. Bardinet told me. “And it hasn’t happened since then.”

Ungrateful though this may sound, I can’t help but feel that the progress of good to excellent to superb vintages, one after the next, has not only spoiled us Bordeaux buffs, but taken away something from the game. We’re getting too complacent to thank nature for smiling on Bordeaux, as we did in 1995, after three of the previous four vintages had proved mediocre to mean. But disaster no longer seems to lurk in the wings.

If Bordeaux weather is indeed turning steadily and permanently more docile, that presents a longterm concern that I heard expressed earlier this year by winemaker Blair Walter of Felton Road winery in Central Otago, New Zealand. His own vineyards, Mr. Walter told me, are at the southern extremity of where wine can be grown. And he is happy for that. If you’re going to have a shot at making great wine, he said, you’d best try to do it on the edge of where wine can be made, where the elements can not only raise you up but slam you down — a winemaker’s take on the adage “no pain, no gain.” Bordeaux was always such a region, but its days on the edge may be numbered. Now there’s a reason to fight global warming.

RECOMMENDED BORDEAUX

Chateau Corbin 2003, St. Emilion ($24) A blend of merlot and cabernet franc, this wine is poised between tradition and modernity: strong spined and yet tender. Many St. Emilion wines are overpriced, but not this one.

Chateau Fonbadet 2003, Pauillac ($25) The wines of this commune are easily the deepest-flavored of the Medoc, and Fonbadet is right in line, its cassis-driven core wrapped in cedar. Since this property didn’t make it into the 1855 classification of Medoc wines, it’s also a bargain.

Chateau Haut Bailly 2004, Pessac ($45) Dark, subtle, and smooth textured, with a finish that swells with essence of black cherry notes. For me, this is the best 2004 of the bunch.

Chateau d’Issan 2003, Margaux ($33) Ever-warmer temperatures in Bordeaux can rob wines of this commune of their signature delicacy. D’Issan remains true to type, even in the hottest vintage ever. With lively aromas and deftly etched red berry flavor, this is a great wine for poached chicken breasts with tarragon.