We had a 30-day Stratosphere warming last Winter Feb 14-March 15.  https://ibb.co/601Xr3H It did downwell to the troposphere to effect the NAO https://ibb.co/GT59g8v Here US temperatures for the most historically effected time-lag: https://ibb.co/82qyFTz Before that we had a Stratosphere warming in January 2021 https://ibb.co/JkdhgnK This is how that one effected temps +time https://ibb.co/d0zFmC1 We also had one in January 2019 https://ibb.