The GFS remains steadfast in suggesting a reversal of zonal winds at 10hPa (60N). Almost every ensemble member shows a #SSW, and the latest deterministic run was the most impressive yet. Should be noted, too, that last nights EPS showed a SPV split at 10hPa as well. #stratparty pic.twitter.com/BtRQgsl5tc

— John Homenuk (@jhomenuk) December 17, 2018