ECMWF Op Model Run / Date of SSW / Zonal Mean Wind:

Dec 29 12z / Jan 5 (day 7) / -2.8 m/s
Dec 28 12z / Jan 5 (day 8) / -0.8 m/s
Dec 27 12z / Jan 5 (day 9) / -0.1 m/s
Dec 26 12z / Jan 4 (day 9) / -2.0 m/s
Dec 25 12z / Jan 4 (day 10) / -2.9 m/s

— griteater (@griteater) December 30, 2020