Have you ever seen those wavy lines on a weather map? Those lines are called isohypses (similar to isobars) and those large waves have a big impact on our weather. Bigger waves mean more strange temperature extremes, like long heat waves, or long periods of freezing weather. If the waves are really large, you can have a day where Ohio is colder than Alaska! We wanted to know how wavy those waves are, and if the waviness is changing over time. To find out, we developed a way to count the waviest waves and then compared data for the last thirty years. Climate change might actually make the waves wavier. And that might lead to more extreme weather—heat waves and cold snaps—in the future.