The best discussion I’ve found of warm weather is this blog post. The way I’m thinking of it now is: Different cities / regions / countries will institute different levels of anti-transmission interventions (social distancing, contact tracing, etc.). As in my other answer, there’s some threshold of intervention which is good enough to stop exponential growth. Some regions will cross that threshold very early on the exponential growth curve, such that only a small fraction of their populations will catch it. Other regions will cross it very late, or not at all, and get it very bad. Warm weather will (more likely than not) help move the threshold in a favorable direction. Based on that blog post above, I think it’s unlikely (but not impossible) that warm weather will move the threshold all the way to “no exponential growth even without any anti-transmission interventions whatsoever”. But that’s not necessarily relevant anyway; there will be interventions! Thus, warm weather will increase the number of regions that avoid problems. (Unless, of course, governments get cocky and relax the interventions in warmer weather, undoing the effects!)
The best discussion I’ve found of warm weather is this blog post. The way I’m thinking of it now is: Different cities / regions / countries will institute different levels of anti-transmission interventions (social distancing, contact tracing, etc.). As in my other answer, there’s some threshold of intervention which is good enough to stop exponential growth. Some regions will cross that threshold very early on the exponential growth curve, such that only a small fraction of their populations will catch it. Other regions will cross it very late, or not at all, and get it very bad. Warm weather will (more likely than not) help move the threshold in a favorable direction. Based on that blog post above, I think it’s unlikely (but not impossible) that warm weather will move the threshold all the way to “no exponential growth even without any anti-transmission interventions whatsoever”. But that’s not necessarily relevant anyway; there will be interventions! Thus, warm weather will increase the number of regions that avoid problems. (Unless, of course, governments get cocky and relax the interventions in warmer weather, undoing the effects!)