The colloquial term is "king tides" or "royal tides." But the scientific term is "perigee tide." Ultimately, it’s the same thing: high tides that cause coastal flooding.

The moon will be in its full phase during the last few weeks of September. During this time, it will also be at its closest point to Earth in its orbit—perigee—which occurs on October 1. During this period, low tides are expected to be lower than normal and high tides higher than normal, causing coastal problems.

On average, high tide is about 2 to 3 feet along much of Florida’s east coast; in some areas, it can regularly be higher. With spring tides, up to one foot can be added to that height. These higher-than-normal tides could cause minor flooding along the coast and coastal erosion.

In cities like Miami, even when it doesn't rain, spring tides cause flooding on busy roads, such as in the city center or downtown. This water flows out through the sewer system and is often mixed with sewage, debris, and pollutants—and since it is saltwater—it can damage car bodies and, in some cases, pose a danger to people walking through it.

Higher-than-normal tides are affecting not only South Florida but also the entire U.S. East Coast and the Pacific Coast. Check the high tide time on our app if you're within 5 miles of the coast.