Why is it so hot so early this year?

Summary

Much of Europe has recorded unusually high temperatures for May, with historic readings in places like France and the UK. The immediate cause is a "heat dome" - a large, persistent high-pressure system that traps warm air and raises surface temperatures. While heat domes are a natural phenomenon, their intensity and frequency are being amplified by human-driven climate change. If greenhouse gas emissions continue at current levels, such early-season heat extremes could become far more common.