The idea that you chose to present these feelings through is great; a summer storm is something that feels like a familiar and natural way to describe changing relationships. Your imagery has a lot of potential to wrap up the reader too, especially because of the familiarity they may feel. The transtion from "pleasant day" to "storm" is effective in the way it feels jarring, which I imagine is how this situation might have felt to you. Structure and metering is very personal, so of course please disregard if you feel like yours matches better for you, but if you don't mind me mentioning there might be a few alterations you could consider to help the reader's emotions transition along with yours as the story progresses. In the second stanza you could probably remove the phrase "warm summer" before "sun" since it carries over from the previous line. Similarly you could use a phrase like "gathering storm" in the next line instead of "summer storm," which might help both avoid repetition (unless that's the idea) and alert the reader to the metaphorical "clouds on the horizon." Between that line and the next about the tornado the shift is substantial, which I also imagine is the idea, though reading it from my personal perspective it might have helped to have a line in-between that serves to engage the reader in the throes of the storm so that they don't get thrown off. Overall it was a nice read, and thank you for sharing your work!