@Typhoon Tip
This piece of literature from several years ago seems to harken back to what you were saying about the Pacific driving the atlantic.
In addition, many studies reported that the tropical Pacific heating have effects on the tropical Atlantic SST anomaly (Wolter 1987; Curtis and Hastenrath 1995; Gallego et al. 2001; Alexander et al. 2002; Huang et al. 2002), which is argued to affect the North Atlantic atmosphere (e.g., Watanabe and Kimoto 1999; Robertson et al. 2000). Therefore, the tropical Atlantic SST may serve as a mediator to link the tropical Pacific SST anomaly and the NA atmosphere.
You guys should have a look at this piece....great job at detailing the divergent la nina evolutions, and the differences across NA.
https://link.springer.com/article/10.1007/s00382-014-2155-z