The roles of planetary and gravity waves during a major stratospheric sudden warming as characterized in WACCM

► Planetary and gravity waves are examined during a simulated major stratospheric sudden warming. ► The sudden warming is characterized by an elevated polar stratopause and mesospheric cooling. ► Filtering of GW and PW-mean flow interaction promote stratopause descent during warming onset. ► Eastward GWs of frontal origin exert a significant forcing after the warming onset. ► As the vortex recovers, a newly formed and elevated stratopause is driven downward initially by PW.