Polar vortex status

The SPV is currently weaker than ERA5 average but is forecasted to become stronger than average (according to GEFS-mean) 18 of 31 members have stronger vortex than average at the last forecast step (2026-05-13T00:00:00) . The zonal mean zonal wind at 10 hPa 60N is today (GFS analysis): -5.9 m/s Weakest zonal wind at 10 hPa 60N in ERA5 record for todays date is: -20.2 m/s 2011 Strongest zonal wind at 10 hPa 60N in ERA5 record for todays date is: 11.9 m/s 2009