I liked the weather thing, too... really started noticing it on my second or third time through this (beta-reading). Check this out:
At the start, Lois and Clark are both unhappy, and not talking to each other about it; the situation is tense and uncomfortable, just like the heat wave. There are some clouds in the sky, but nothing's happened yet. L&C go for a walk, finally start talking, reach an understanding... and it starts raining. They go back to the house; it's still cloudy out, and they still have a few things left to talk about... and then at the very end, when L&C have resolved everything and are happy, we see the sun emerging from the clouds. I just think that's really cool
PJ