The National Hurricane Center is tracking a tropical wave in the eastern Atlantic on the heels of Hurricane Erin that could strengthen into a depression later this week.

Hurricane Erin strengthened 85 mph in 24 hours to a 160 mph Category 5 hurricane putting in fourth place for rapidly intensifying storms.

The Atlantic basin includes the northern Atlantic Ocean, Caribbean Sea and Gulf of America, as the Gulf of Mexico is now known in the U.S. per an order from President Trump. NOAA and the National Hurricane Center are now using Gulf of America on its maps and in its advisories.

Hurricane Erin on Monday bulked back up as a major Category 4 storm with an increasing wind field as it moved near the Bahamas. Meanwhile, the National Hurricane Center increased the odds a system

This wave is so new that the hurricane center has yet to dub it an “invest,” a technical term that kicks off heightened scrutiny and allows global hurricane models to pick up the system and begin issuing estimated forecast tracks.

Tropical Storm Erin continues its westward path across the Atlantic, expected to become a hurricane Aug. 15, and a major hurricane by Sunday morning.

Hurricane Erin is forecast to remain well offshore but still bring hazardous currents and possible erosion like previous offshore hurricanes before it.