Great stuff from Allan Huffman. Today's 12z op ECMWF and EPS mean both show the 10mb U wind turning negative, meaning a change to an easterly wind direction over the polar regions and an #SSWE with 41 of 50 EPS members (82%) showing this reversal with 11/25 the day with the most negative members. Sudden Stratospheric Warming Events, can weaken the tropospheric polar vortex, allowing for increased high latitude blocking (-AO) and the enhanced risk for arctic air discharge into the mid-latitudes (North America, Europe, East Asia). A late November SSWE is relatively rare, and COULD help favor a cold start to meteorological winter(December). The last November SSWE was in 1968. Sent from my SM-G998U using Tapatalk