Didn't see the question asked about early SSW events and any correlation to a prolonged weak PV. This is the chatgpt response lol.
1. Early SSWs = Weaker Mean Vortex Winters
Winters with an early (November–early December) SSW typically show a weaker-than-average stratospheric polar vortex throughout the rest of the season.
Once the vortex is disrupted early, it often fails to fully recover for the remainder of winter.
Example years: 2009–10, 2018–19, 2023–24 (minor) — all featured early or midwinter SSWs followed by persistently weak vortex conditions and stronger planetary wave driving later on.
2. Frequency of Subsequent SSWs or Vortex Disturbances
Multiple major SSWs in a single winter are rare, regardless of timing (the stratosphere needs several weeks to recover).
But early SSW years often have enhanced minor warmings or continued wave breaking, meaning more disturbed stratospheric conditions overall.
Statistical studies (e.g., Charlton & Polvani 2007, Butler et al. 2017) show that if the first SSW occurs before January, the likelihood of another major SSW in the same season rises slightly — but still remains low (≈15–25%).
So:
Early SSWs don’t make them frequent per se, but they often signal a weaker, more unstable vortex that is more prone to further disturbances.
).
