Pressures over Greenland are lowest in the winter and highest in the summer. Winter pressure spikes are often associated with negative NAOs ... 2009-10 was a doozy. Winter 2020-21 will perhaps give us an indication of what is to come. Summer pressure also moved higher in the low solar period of 2008 to 2010 and has yet to return to its previous lower levels. Large negative summer NAOs are partially due to this change, and while its never talked about, may have something to do with the extreme precipitation patterns in the Med. and N African areas.
The normally dry North African and the Middle Eastern countries are often not set up to deal with these events ... engineering issues. I noted in Jeddah, Saudi Arabia, that culverts and standard drainage systems seemed missing in whole sections of the city. In very rare, heavy rain events, whole sections would be flooded to the level of the lowest swale in the road system. Pumper trucks would be dispatched to suck up the very deep "puddles" (lakes) that developed. Since Jeddah is very flat, these events could cover large areas. Since Princes often owned the construction companies that sucked off the public purse, no one would force them to pay for anything they didn't have to. More princes than you could shake a whole forest at.
A totally semi-related aside. I spent 25+ years learning the fine art of driving, before I went to Saudi Arabia and REALLY learned how the drive.