Weather Disasters(WDs) have played a role in promoting migration in several episodes, but it is unclear if their role is systematic or idiosyncratic. The answer to this public policy question is very important because the intensity, frequency, and scope of WDs are observed growing as climate change progresses in this century under business as usual. Known empirical studies mainly associate essential immigration inflows with violence, economic and institutional development in origin countries. This paper develops a theoretical framework and statistical model that anticipates potential for varied migration responses to WDs across countries and over time, and examines public/economic policy levers that might mitigate or facilitate these responses. Our econometric analysis utilizes unbalanced panel data set for migration flows between 190 origins and 190 destinations across the period from 1980 to 2009.The results suggest that the effect of intensity and incidence of WD on migration flow is nonlinear and may vary in both magnitude and direction due to other factors such as country-specific personal income or international aid, for example. The empirical results are used to estimate projections of migration flows to 2060 under several conservative scenarios. Finally, we discuss implications of our findings for illegal immigration, the possibility of immigration-induced violence, and policies of adaptation to and mitigation of climate change.