In September of last year, heavy rainfall from Hurricane Ida reached the Northeastern U.S., killing at least eight people and flooding enough New York City subway stations that the whole system had to shut down.

Now, a new study warns that scenes like this could become more common as the climate crisis continues. The research, published in Nature Geoscience, found that hurricanes and cyclones could form and intensify in mid-latitudes this century, putting major population centers like New York, Boston and Beijing at risk.

“This research predicts that the 21st century’s tropical cyclones will likely occur over a wider range of latitudes than has been the case on Earth for the last 3 million years,” study author and Yale University physicist Joshua Studholme said, as the Hartford Courant reported.

Tropical cyclones, as their name suggests, typically form over the warm waters of tropical oceans. Storms like Ida that form in the Caribbean and then move north can still do massive damage to mid-latitude population centers. But the new study suggests that these destructive storms could actually begin over mid-latitude waters. One example was 2020’s subtropical storm Alpha, which was the first ever tropical cyclone to make landfall in Portugal.

These dangerous storms could shift because the difference in temperature between the tropics and the poles will decrease as the climate warms, weakening the jet stream that typically keeps hurricanes and cyclones near the equator.

“As the climate warms, that sort of jet stream activity that happens in the middle latitude will weaken and in extreme cases split, allowing this sort of cyclone formation to occur,” Studholme told BBC News.

The researchers based their predictions on satellite data, future weather and climate projects, and the physics behind atmospheric convection and planetary winds, the Hartford Courant explained.  They also looked at models of the distant past, when Earth was warmer, such as the Eocene (56 million to 34 million years ago) and the Pliocene (5.3 million to 2.6 million years ago). Those models showed tropical cyclones forming and intensifying at mid-latitudes.

Read the full article about hurricane migration by Olivia Rosane at EcoWatch.