Which tropical storm was reported to be forming over the Caribbean?

Tropical Storm Erin is identified as the storm that was forming over the Caribbean. This name aligns with the patterns and criteria used for naming tropical storms in the Atlantic basin, where the Caribbean is located. Each year, the National Hurricane Center and various meteorological organizations monitor storm activity, and names are assigned according to the established list for that specific season. Erin's development over the Caribbean corresponds with the typical patterns of formation in that region, especially during the peak of the Atlantic hurricane season.

In the case of the other storms—Alex, Fiona, and Ian—these names correspond to separate storms that occurred in different contexts or years, and their formation locations or timelines do not match the criteria established for Erin in this specific instance.