Heatwaves will occur earlier and more often in the future, the UN’s weather and climate agency said on Friday, pointing to the pre-summer heatwaves already scorching parts of Europe. “What we are witnessing today is unfortunately a foretaste of the future,” said Clare Nullis, spokeswoman for the World Meteorological Organization (WMO). The extremely high temperatures that have spread from North Africa across southern Europe and are expected to hit Switzerland and Germany this weekend are more typical for July or August, the WMO said. In some parts of Spain and France, temperatures have recentl…