One could argue that westerly flow causes our biggest heat outbreaks and that the onshore flow happens because there are weaknesses in the ridge. I've seen when the high is really strong it overcomes sea breezes which is when we get our best heat.
Do you actually rank 2020 higher than 2010 though? 2010 was basically our 1995-96 of summers for the most heat across the entire region (we are after all a coastal region) and was also the hottest summer on record by summer average.
I'm not sure how representative LGA is of our area because of its cramped congested location, I'd rather use an average of all the airports. And if you judge summers by peak heat, I dont see any 102-103 temps like we had in 2010 and 2011, which is a true indication of how dominant a ridge is. 2010 is like MJ and 2020 is like Lebron. Sure Lebron had a longer career but at his best MJ was a better player.
I actually think EWR is more representative of our area than LGA, because the years in the EWR list are more of what I remember as being extremely hot. All the summers prior in the EWR list are what I would call extremely hot.