The Three Phases of Helene
- Phase 1 - Record Tampa Bay Storm Surge: Locations south and east of Helene's category 4 landfall near Perry, Florida, through the Tampa Bay metropolitan region achieved record coastal storm surge levels, breaking records by 2 to 3 feet. National Flood Insurance Program (NFIP) county take-up rates north of Tampa are generally less than 5% of all properties.
- Phase 2 - Strongest Hurricane to Make Landfall in Big Bend Region of Florida: Helene rapidly intensified through landfall, eclipsing the 1896 Cedar Key hurricane as the strongest to make landfall in the Big Bend Florida region since records began in 1850. From an industry insured loss perspective, the eye of Helene passed just east of Tallahassee, Florida, which likely eliminates higher insured loss scenarios (excluding NFIP) in excess of USD 10 billion. As a result, the vast majority of wind losses will likely be retained by primary insurers rather than ceded to reinsurers. However, the record forward speed of Helene at landfall will result in meaningful inland insured wind losses; over 3 million customers are experiencing power outages as of 7 a.m. EDT Friday, September, 27, spanning from Florida through the Carolinas.
- Phase 3 - Generational Flood Event in Southern Appalachian Mountains: Well ahead of landfall, heavy rainfall spread across the southeastern US with continued heavy precipitation overnight as Helene tracked across Georgia. Many river gauges are expected to see top-five river crests, with the Swannanoa River in Biltmore, North Carolina, exceeding the prior record height established in 1916.
- What is Next? Helene will slow down dramatically and stall over the southern Appalachian Mountains through the weekend as the storm merges with a mid-latitude cutoff low pressure system. Beyond Helene, Isaac became the sixth hurricane of the 2024 Atlantic season in the central Atlantic with no threat to land. An organizing disturbance in the deep tropics will likely become Tropical Storm Joyce over the weekend; weather models indicate Joyce will also stay out at sea.
- Noteworthy Hurricane Helene Statistics
- Record forward speed of a landfalling hurricane in the Gulf of Mexico (Source: @catinsight).
- Helene rapidly intensified rapidly through the final 24 hours before landfall; this is the eighth hurricane to do so since 2017 (Harvey, Michael, Laura, Ida, Ian, Idalia, Francine); only 6 storms accomplished this feat from 1982 to 2016.
- All-time record storm surge levels along the west coast of Florida as far south as Tampa Bay.
- Strongest landfalling hurricane on record for the Big Bend region of Florida.
- Sixth year since 1850 the U.S. has experienced four landfalling hurricanes joining 1886, 1909, 1985, 2005 and 2020 (Source: @philklotzbach).
- Helene marks the eighth category 4 or category 5 hurricane to make a U.S. landfall since 2017 (Harvey, Irma, Maria, Michael, Laura, Ida, Ian). Prior to 2017, eight category 4/5 hurricanes made landfall between 1960 and 2016, a 57-year stretch (Source: @DrJeffMasters).
- Helene was the ninth-lowest pressure of a landfalling Florida hurricane since 1850.
- 3 of the 5 most recent landfalling US hurricanes have made landfall in the Big Bend of Florida, one of the least populated areas of the entire U.S. coastline; since 2017 nine major hurricanes have made landfall in the Gulf of Mexico (Source: @burgwx).
This is the last report that will be issued on Hurricane Helene. Please access the links below for up-to-date information as Helene dissipates over the Southern Appalachian Mountains.