US: Storm Sally causes flooding in Florida, Alabama and Georgia as it weakens over land September 17 /update 5

Event

The remnants of Hurricane Sally brought over a foot (305 mm) of rain to parts of Florida and Georgia on Thursday, September 17, having weakened into a tropical storm and then a tropical depression as it moves over land. The storm has affected a wide area from eastern Alabama through to central Georgia, having made landfall near Gulf Shores (Alabama) on Wednesday, September 16, as a Category 2 hurricane. Almost 500,000 homes and businesses are without power in Alabama and Florida and bridges and roads have been damaged, causing disruption to transport. One person was killed and another reported missing in coastal Alabama during the passing of the storm system. The storm is forecast to continue to weaken as it tracks northeastward through Georgia and into the Carolinas through Thursday and Friday, September 18, before fully dissipating.

Heavy rainfall, residual disruption, and further disruptions to transportation, business, and utilities are likely in the coming days. 

Context

The Atlantic hurricane season runs from late May through to the end of November, with activity typically peaking in late August and early September. Numerous tropical storms form in the Atlantic Ocean during this period, with most affecting the Caribbean, the Gulf of Mexico, and the east coast of the United States. Although communities in the region are generally well prepared for adverse weather conditions during the hurricane season, severe storms bring a significant risk of flooding and infrastructural damage.

Organized tropical activity tends to peak in August and September. Storms tend to flood sections of highways and cause dirt-based roads to become temporarily impassable. More organized systems, depending on intensity, can prove catastrophic in terms of tidal surge, wind damage, flooding, and mudslides.

Advice

Those in the above areas are advised to monitor local weather reports, avoid areas directly affected by flooding, confirm road conditions before setting out, and adhere to instructions issued by local authorities.