Courtesy to Isotherm, he and I had a small conversation on the disruption of the global jet stream patterns due to the emergence of changing Hadley Cell and Mid-Latitude Cell circulations. As SSTs continue to warm poleward due to the background state and changing climate, we see more convection which acts to disrupt the typical Hadley Cell circulations we know. Typically we see rising air at the ITCZ which spreads poleward and subsides around 30N which creates the Horse Latitudes. With convection being able to fire further north, the Hadley Cell circulations expand which create stronger gradients and subsequently strengthen the mid-Latitude cells. For the United States, that means the Pacific Jet stream becomes stronger. What I mean as "this isn't new" is the warmth of the Pacific and overall global oceans. We've seen warmth of our oceans for awhile now. However, are we finally entering the critical time where we truly do start to see global jet stream changes? Are winters going to be the same again? Or will we see more variability resulting in bigger and more extreme winter events? Have we already seen those changes? I don't know the answers to those questions, but I do know that in theory the global jet stream patterns should be or have already changed in the changing climate.