I think the problem is that the OP is only taking into account weather at exactly two points in space-time and fails to see the big picture. Most people also think The Weather Channel is accurate and don't even know about aviation weather sources.

There's an old adage that applies here - Time to spare, go by air! If you care about being somewhere (a show, a cruise, etc), book at least a day or two ahead unless you're willing to acknowledge the risk.