Timeline of Hurricane Helene (September 24-27, 2024)

• September 20-22: A Central American Gyre (CAG) develops, bringing heavy rains to portions of Nicaragua and Honduras as it moves slowly northward.
• September 23, 1200 UTC: The large circulation of the CAG straddles Central America and the northwestern Caribbean Sea. Deep convection begins to organize near a mid-level vorticity maximum about 130 nautical miles south of Grand Cayman. The system lacks a well-defined low-level center necessary to be a tropical cyclone.
• September 23, 1500 UTC: The National Hurricane Center (NHC) initiates potential tropical cyclone advisories as the system is expected to become a tropical cyclone and bring tropical storm conditions to land areas within the next couple of days.
•  ...