It's possible that the criteria for a major sudden stratospheric warming (SSW) will be marginally reached on Tuesday 16 January (daily-mean 10 hPa 60°N zonal-mean winds reversing to easterlies).

However, this event doesn't come with the usual fanfare of an SSW... 🧵 pic.twitter.com/8RZtY926Zk

— Dr Simon Lee (@SimonLeeWx) January 16, 2024