There has been an absolutely spectacular change in the forecast for parts of the N Hemisphere.
In terms of N American weather regimes, this appears as a shift from a persistent Greenland High (with almost no chance of Pacific Ridge), to Alaskan Ridge followed by Pacific Ridge! 🧵 pic.twitter.com/OcrQMg1qcb

— Dr Simon Lee (@SimonLeeWx) February 14, 2024