Polar vortex status

The SPV is currently weaker than ERA5 average but is forecasted to become stronger than average (according to GEFS-mean) 17 of 31 members have stronger vortex than average at the last forecast step (2025-12-30 12:00:00) The SSW probability in GEFS is: 0%. The zonal mean zonal wind at 10 hPa 60N is today (GFS analysis): 16.3 m/s Weakest zonal wind at 10 hPa 60N in ERA5 record for todays date is: -7.4 m/s 1987 Strongest zonal wind at 10 hPa 60N in ERA5 record for todays date is: 53.6 m/s 2015