Summary. 2018 will be the warmest vintage we have experienced. It is hard to comprehend how much hotter than average this season is but the statistics will break records. September and early October were average apart from some heavy frosts pre-budburst. Temperatures increased to above average from mid-October and have stayed above average. A cold snap on 8 November brought heavy snow to Otago but fortunately winds and cloud kept the expected frost away and the snow melted quickly. November, December and January temperatures were well above average and vine growth advanced rapidly resulting in an early and successful flowering. Grape development is well advanced and we expect to be harvesting at least two weeks ahead of normal.
September started with three consecutive frosts getting as low as -5 degrees. Otherwise the month was was normal to very slightly warmer than average.
October started out normal but from mid October temperatures were high for this time of year. We had six consecutive days peaking over 25 degrees (28 Oct to 2 Nov). We have not seen this level of heat, this early in spring, before. Budburst was in the first week of October but variable between blocks.
November temperatures continued above average with little rain. Temperatures averaged 3 degrees above normal. The weather patterns were predominately coming from the northwest with warmer temperatures with very little cooler southwest weather. With the heat, vine shoot growth bolted and floresence development was well advanced and hence flowering early. Flowering was complete by 30 November which is 2-3 weeks ahead of average.
December continued with temperatures well above average. The prevailing warm northwest winds and sea temperatures 2-3 degrees above normal (see chart below) were reasons for the above average temperatures. 27 December provide a surprise when overnight temperatures dropped briefly below zero degrees.
January temperatures were literally off the chart. Our historical data chart scale did not go high enough. January heat accumulation, measured as growing degree days, was over 60% higher than our average. Veraison (grape colour change) came two to three weeks early. Rapid ripening is not ideal for Pinot Noir and fortunately peak temperatures at the end of January have abated.
February has cooled to more normal temperatures. This is good and will slow ripening. Grape picking is still expected to start two weeks ahead of normal.