Increases in rainfall, temperatures might involve a higher probabilty of accidents in certain areas, but the expected trends in the change of any of these variables will take decades, so ITS changes will be ("naturally", if naturally is a appropiate word) faster than climate change.
Most of the simulations about climate change are predicting a high probability of increases in extreme events (storms, heat waves...). But they are so different in sign and range if you consider their spatial implementation, that it is impossible to have a single answer. There will be increases in storms in some arease, but decreases in others, There will be more ice during winter in certain places, but winters will be hotter in others... Since Intelligent Transportation Systems are designed in order to cover all the populated areas in the planet, it would be impossible to decide a single direction about the future. Things will be different due to climate change, but they have an extremely high spatial variability.