Recent California Heat Wave Caused Napa Wine Grapes To Wither, Affecting Wine Production

Last week, a record heat wave stifled nearly all of California. Because of the intense temperatures, vineyard owners worry that yields of Napa wine grapes will drop this year. That potentially means some California wines may be harder to find when ready to sell.

napa wine grapes
Photo: Lee Coursey on Wikimedia Commons

According to the San Francisco Chronicle, the recent heat wave sent this year's yield expectations from average to uncertain. Grapes don't typically acclimate to intense heat, shriveling into raisins when in duress from it. Considering that the heat episode reached 110 degrees and didn't cool down at night, it's safe to say that many Napa wine grapes are now raisins.


One vineyard owner told the Chronicle that as much as half of her crops are now raisins, eliminating them from usage as wine. Additionally, some grapes may be overripe or partially dehydrated, which would ruin their flavor for wine production. Thus, it's really unknown how many grapes Wine Country really lost.

Not all wine grapes are going to suffer from this, however. Some wine varieties, like Cabernet Sauvignon, have already been harvested when peak ripeness was reached a few weeks ago. Pinot Noir grapes were the closest to ripeness when the heat wave hit, so many of those got harvested a little early to preserve flavor. Bordeaux wines and Cabernet, which aren't ripe yet, definitely suffered, however.

For us, this means that we may be seeing some changes in availability of 2017 California wines once they make it into stores. That could potentially affect price as well. However, we'll have to wait and see how much of the wine crop was truly devastated to know for sure what wines and how much of them were lost to the heat wave.