Port producers in the Douro Valley expect yields to be down this year after being hit by hail, and extreme heat, in the past two months. After an unusually hot May and a cool early June, temperatures soared into the low 40s Celsius during the last weekend of the month, inflicting the worst sunburn in living memory on the vineyards. Writing in his Graham’s Port blog, Symington Family Estates viticulturist Miles Edlmann said the heat particularly affected the Vilariça Valley, which had also been damaged by hail earlier in the month.