Problem is that it isn’t that simple. The general fact we do know is that the atmosphere will be more energetic and, on average, the globe will be hotter. The more energetic facet means more weather activity and changes to various currents. So local weather may be more impacted by a change in wind current temperature wise. The change in storm activity may be the bigger concern rather than temperatures. We don’t know how much viable agriculture will be possible or exactly where it will be. Also there’s the question of soil quality. It’s a dangerous gambit to assume a straightforward “Lots of snowy land now means lots of agriculture in a warmed globe”.