I always thought the STJ stuff was a result of convection in the east pac. For instance if Nina was west based, you wouldn't have such cool waters in the eastern Pacific and naturally there will always be some convection there in the tropics.
This is pretty cool. I know this freaks many out, but this is good to see when the species is endangered.
https://boston.cbslocal.com/2021/09/15/timber-rattlesnake-blue-hills-hiker-video/