The national heat plan has been activated for the second time this summer as temperatures are set to reach between 30C and 35C in most parts of the Netherlands. The meteorological office KNMI has issued code yellow warnings for the inland provinces of Overijssel, Gelderland, Noord-Brabant and Limburg, for Wednesday, and Thursday and Friday. On Saturday there will be a brief respite, with maximum temperatures of 25C, but new highs of 33C are forecast for Monday. The national heat plan is invoked if there is a serious risk of temperatures above 27C for four days or longer. Last month the KNMI issued a red alert for heat for the first time.