How Hurricane Harvey’s Record-Setting Rainfall Is Happening Right Now

“The worst-case scenario for a storm is where it develops in the ocean, strengthens as it moves over land, and then migrates to make landfall right where the directions of the prevailing winds change: at around 30 degrees latitude. The greatest flooding and devastation occurs when the storm either remains stationary, right on a coastal area for a long time, or when it moves along a coastal region, constantly being fed by the ocean waters as it does so. Houston, Texas, is located right at 29.8° N latitude, right by the gulf coast; it is at the right location, unfortunately, to experience this perfect type of storm. ”

As I write this, the gulf coast is currently being battered by Hurricane Harvey, with a few locations already having accumulated more than three feet of rainfall. This storm shows no signs of letting up anytime soon, as it’s forecast to remain roughly where it is for days to come. This is being billed as a 500-year-storm, but the truth is far scarier and more sobering: this should be exactly what you’d expect for a city located where Houston is. The way hurricanes form, along with other tropical storms, is when fast-moving winds occur over high-temperature ocean waters. As global temperatures have increased, so have the severity of hurricanes. When one of them makes landfall and rises in latitude, the critical transition occurs at 30° north or south of the equator, where the prevailing winds change direction. As Hurricane Harvey sits right on that boundary, it seems poised to remain where it is for up to a week, potentially leading to even more catastrophic flooding than occurred during Hurricane Katrina.

The science is sound, robust, and legitimate, but the disaster is real and going on right now. Sadly, the worst may still be yet to come.