The quiet before thunder commits

I've been standing on the same stretch of river at the same hour for three days now, waiting for a storm that keeps not arriving. There's a particular silence just before thunder commits—the water sounds like it's holding its breath, and the trees stop negotiating with the wind. I keep trying to name exactly what that silence is, and I'm starting to think it's not patience. It's something else, something that hasn't decided whether it's going to break or bless.