(Wines&Vines) - The solid accumulation of heat units means vintners are hitting the trail to vineyards the Horse Heaven Hills a few days earlier than usual this year to round up ripening grapes.

Crews picked clusters of Marquette at Paul Champoux’s vineyard last week, while Mercer Wine Estates logged what looks to be the earliest-ever harvest of Sauvignon Blanc from its vineyards Tuesday (Aug. 26).

“We’re about four days ahead of where we were last year,” said Rob Mercer, president of Mercer Wine Estates.

The previous benchmark for an early harvest was Aug. 28, but warm temperatures and clear skies saw the tally of growing degree-days hit 2,538 as of Aug. 24, putting the AVA on track to top the long-term average of 2,989 and perhaps even the 2013 tally of 3,164 (state-wide numbers are available via Washington State University).

Mercer expects to harvest Sauvignon Blanc for its own wines (and potentially Pinot Gris) once September arrives. Grapes picked this week came in at approximately 21º Brix, while Mercer prefers something closer to 23º Brix for its own wines.
Though it doesn’t take the good weather for granted, the season to date is allowing Mercer greater leeway with scheduling and handling of its grapes.

“We try to be consistent with our style, so in a warm year like this we definitely have the ability to hang the fruit for a little bit longer,” Mercer said. “We have a little more flexibility to take stuff at its premium, and we’re not quite as bunched up toward the end of the season.”

Mercer expects to harvest 5,500 tons this year, the majority going to Ste. Michelle Wine Estates. “The yield expectations are in line with long-term averages, and things look good. So there doesn’t appear to be any reason to feel things are going to be short at this point,” he told Wines & Vines.

Similarly, Ali Boyle expects harvesters to start bringing in Sauvignon Blanc for Alexandria Nicole Cellars as early as this weekend. While summer rains provided some concern regarding mildew, the famous winds of the Horse Heaven Hills swept away most of those fears fairly rapidly. “If anything we were worried about things being a little too heavy this year,” she said. “It’s a good problem to have.”