Climate change will increase the size of stalled high-pressure weather systems called "blocking events" that have already produced some of the 21st century's deadliest heat waves, according to a Rice University study.

https://www.sciencedaily.com/releases/2019/11/191113075107.htm

Atmospheric blocking events are middle-latitude, high-pressure systems that stay in place for days or even weeks. Depending upon when and where they develop, blocking events can cause droughts or downpours and heat waves or cold spells.