(NATIONAL) — The tropics are past the climatological peak in early September, but development is still common this time of year. As of Sunday, Sept. 28, the Atlantic is busy with Hurricane Humberto and Tropical Storm Imelda, both spinning.

Hurricane Humberto is a Category 4 storm east of the Bahamas with winds near 150 mph. It will stay out to sea but is sending large waves toward Bermuda and the U.S. East Coast.

Tropical Storm Imelda, just northwest of Cuba, became a tropical storm today and is expected to strengthen into a hurricane early this week. It will move north, then turn away from the Southeast by midweek.

When two storms are in the same part of the ocean, meteorologists sometimes watch for something called the Fujiwhara Effect. This is when tropical systems begin to influence each other’s paths and can even spin around a common point. It’s rare, but it can make forecasting more challenging. Right now, Humberto and Imelda are close enough that the idea comes up, but the latest forecasts show they will mainly go their own separate ways.

For the United States, the biggest impact will be rough surf and dangerous rip currents along the East Coast later this week. For the rest of the country, including here in Colorado, these storms will not bring direct impacts.