In the medium-term, the stratospheric polar vortex will undergo some intensification -- from weaker to stronger-than-normal 📈 The stratospheric Aleutian ridge, which has been causing the weaker vortex recently, is expected to dissipate. 🧵 [1/6] pic.twitter.com/CaFdNsJfNp

— Dr Simon Lee (@SimonLeeWx) November 4, 2021