Early Wednesday morning, Hurricane Sally struck the Gulf Coast from Mississippi to the Florida Panhandle as a Category 2 storm. It’s expected to dump a devastating 20 inches of rain as it continues moving over land more slowly than the average person walks—about 3 miles per hour.

Last month, Hurricane Laura struck southwest Louisiana and Texas, trotting onshore at 15 mph as a Category 4 storm that rapidly lost steam once over land. (See photos from a Louisiana town struggling to rebuild after Laura.)

Twice in the past three days, Sally built wind speeds in just a few hours—the storm “rapidly intensified”; on Monday and then again late Tuesday into Wednesday morning. Laura also rapidly intensified—from a tropical storm to a