As temperatures creep up across the winemaking world, many winemakers, especially in traditionally cooler climates, such as those in Oregon and Washington, are having to figure out how to keep alcohol levels in check. In Oregon in 2009, for example, cumulative growing degree day (GrDD) values for many areas were up 4 to 14 percent over 2008. (GrDD is a heat index that helps assess crop development.) By 2016, heat was becoming a norm in Oregon. Bud break was early, followed by a brief heat spell that tapered off. And overall, the summer had fewer heat spikes than in 2014 and 2015. This level of heat makes for some round, supple wines, but when winemakers want wines that are cool and fresh, racy and pure, and perfectly in balance, they may be faced with tough decisions: Take the higher heat that Mother Nature is dishing out and roll with it, or find a way to keep alcohol levels in check, or reduce the alcohol to create the style of wine they desire.