What Does This Warm Summer Mean for Harvest 2014?

Thus far, 2014 has been an extremely warm spring and summer in Oregon's Wine Country. People ask us frequently what this means for Harvest 2014. In short:

  • Oregon Wine Country has been about 5 degrees warmer than normal and growing season markers are running near record levels due to all this sunshine. We measure this in Growing Degree Days (GDD), which is a measurement of heat accumulation that predicts when harvest will occur and provides a comparison to prior vintages. Click here to read a simple definition of GDD.
  • The GDD Data: We can compare this point in the 2014 vintage to other vintages, thanks to Gregory V. Jones, Professor of Geography and Environmental Science, Southern Oregon University. How many GDDs would we expect to have on this date (i.e., how many heat units have we had as of the beginning of August and how does this compare to other vintages)? As of 8/31 in any given year, the average GDD in the Willamette Valley is 1703, according to the historical average that Professor Jones has tracked from 1981-2010. However, as of 8/31, the GDD in 2014 was 2082, representing a 22% increase over average! We are even 8% higher than a recent warm vintage (2013). Click here to see this GDD data courtesy of Professor Jones.
  • Predictions for the Wine: We would expect wine from this vintage to be fruit forward, rich, and higher in alcohol, since we are getting the heat to develop the sugars. Think 2006 and 2009 in Oregon. Since sugar and acid development are basically inverse correlations, warm vintages leave us hoping that acids will be decently balanced.
  • Predictions for Harvest: We are expecting an early harvest, likely in mid September. As a note, the earliest we have ever started harvest was in 2013 on September 20th. The latest we have ever started harvest was in 2011 on October 24th.
  • That said, it is all about September. That is when we experience the greatest variability and the weather in that month will dictate when we ultimately harvest. At this point, the Climate Prediction Center models suggest a warmer than average September-October, but there is no clear signal from the data on precipitation.

For now, things look good and we are hoping for cool nights and a bit of mild rain. As is always the case when we think about the weather, our fingers are crossed.