Andrea formed unusually far to the north and east compared to previous first named storms, over an area of warmer than average ocean waters.

The 2025 Atlantic hurricane season is off to a relatively slow start, with the first named storm forming, on average, around June 20. The main factors preventing storm formation have been hostile winds in the upper atmosphere as well as thick plumes of dust moving westward off the Sahara Desert.

Tropical storms need warm, moist air to form as well as warm ocean waters to tap for energy. Saharan dust tends to inhibit storm formation by carrying dry air with it and reflecting incoming sunlight, thereby causing sea surface temperatures to decrease.

Despite the slower start, especially compared to recent unusually active seasons, the 2025 Atlantic hurricane season is still expected to be above-average.

NOAA’s seasonal outlook calls for up to 10 hurricanes when an average season would see seven. Three to five of these storms are projected to be major hurricanes of Category 3 intensity or greater.

Climate change is not thought to be increasing the number of Atlantic storms each season, but it is making those that form produce heavier rainfall and undergo more frequent and extreme bouts of rapid intensification.