Today's topic is primarily for people familiar with both the military tech used for crowd control and some experimental japanese weather control systems. In particular the military has developed a system that boils the water just under your skin to the point no rational person would stay where they are by choice but is otherwise non-lethal. In japan on a small relatively uninhabited island for the last couple years there's been an experimental weather control system being developed and tested. The island itself is mostly stable all year round naturally staying within a specific temperature range which helps to determine the effectiveness of the system. Apparently they've been successful in making it rain when they want to, which could suggest they can do quite a bit more if they want to.
Now consider the principals of each and how we know thermodynamics work in response to specific electromagnetic frequencies and wavelengths. You could in theory create a fast acting freeze ray if you're not worried about cell damage that comes from rapid cooling and expansion. Which is to say if you're not using it on something living, such as people or animals as a primary example. These systems are both relatively small and very portable, given enough of them we could have a much greater control over the weather if we really wanted.
Consider though the effects this might have on the world if we could control the global weather. Would they be to our advantage or disadvantage? What repercussions could come from manipulating such a large natural system to such a great extent? I'm equally fascinated and horrified by the potential some of our wildest tech has to offer these days.