Historically low temperatures in the northeast have been affecting agriculture growth across the board, even ice wine grapes. Winemakers in the Lake Erie wine country are harvesting sooner than normal to avoid further damage. Ideal harvesting temperatures for ice wine grapes is between 15 and 19 degrees F. Average temperatures this season have been closer to 11 degrees F.
Consistently lower temperatures can cause an increase in sugar content, resulting in a syrup-like pressed product. There are production solutions available to balance this out, including harvesting in the early evening versus later at night and thawing the grapes afterwards. Extreme cold could cause long term damage to the vines, though snow can act as an insulator when covering the crops. The vines will be closely assessed in the early spring for damage from the harsh winter temperatures.
Source: WGRZ, January 2018