As hurricanes Florence, Isaac, and Helene take shape across the Atlantic and barrel toward the East Coast of the United States, a huge amount of behind-the-scenes activity is going on around them.

Scientists are looking at them from above and below, and attempting to give the public an inkling of the storms’ impact. It’s a massively complicated task and one that hasn’t advanced as far as you might imagine. In fact, to this day, the best way to know what’s happening inside a hurricane—and glean its future—is to fly a plane right into the swirling gyre.

Predicting hurricanes is very difficult. The reasons why are complicated, but as we learned in the first part of this series, it has a lot to do with the fact that while there is a very specific recipe for making a hurricane, there’s no clear one for what makes a hurricane strengthen or weaken. Those are areas of active scientific research. For example, Rosimar Rios-Berrios, an atmospheric scientist at the National Center for Atmospheric Research (NCAR), is currently studying how the distribution of clouds can make a storm increase in strength. One of her findings (which has also been found by other scientists studying this) is that for a storm to gain strength, the clouds must wrap themselves evenly around the eye, the center of low pressure, before it can intensify. “If they don’t wrap around, you can say that, for the next 12 to 24 hours, it’s not going to become intense,” she says.