Yeah pretty much what Will said. It will help keep ern regions cooler, and then that interface where erly anomalies and wrly anomalies meet, would trend east. For simplistic terms, that interface is probably where you have anomalous convection. Keep that east of the maritime continent would be a good thing.
So if you look at the erly anomalies and pretend there is a trend line going from top to bottom, you'll see what he means. The lower part is a forecast, but sometimes those forecasts are not accurate.
Mike V showed a graphic of the background easterlies, slowly migrating east over the last few months. I thought that was a good thing to see. I can't right now, but someone can link that.
How would April and May be better predicting the NAO? I don't understand that logic. To me, that is more of a product of late winter strat warming, where we are in QBO ascension, descension, and also ENSO state.