Meteorological history | |
---|---|
Formed | September 11, 2020 |
Extratropical | September 17, 2020 |
Dissipated | September 18, 2020 |
Category 2 hurricane | |
1-minute sustained (SSHWS/NWS) | |
Highest winds | 110 mph (175 km/h) |
Lowest pressure | 965 mbar (hPa); 28.50 inHg |
Overall effects | |
Fatalities | 9 (4 direct, 5 indirect) |
Damage | $7.3 billion (2020 USD) |
Areas affected | The Bahamas, Cuba, U.S. Gulf Coast, Southeastern United States |
IBTrACS | |
Part of the 2020 Atlantic hurricane season |
Hurricane Sally was a destructive and slow-moving tropical cyclone that was the first hurricane to make landfall in the U.S. state of Alabama since Ivan in 2004, coincidentally on the same date in the same place. The eighteenth named storm and seventh hurricane of the extremely active 2020 Atlantic hurricane season, Sally developed from an area of disturbed weather which was first monitored over the Bahamas on September 10. The system grew a broad area of low-pressure on September 11, and was designated as a tropical depression late that day. Early the next day, the depression made landfall at Key Biscayne and subsequently strengthened into Tropical Storm Sally that afternoon. Moderate northwesterly shear prevented significant intensification for the first two days, but convection continued to grow towards the center and Sally slowly intensified. On September 14, a center reformation into the center of the convection occurred, and data from a hurricane hunter reconnaissance aircraft showed that Sally had rapidly intensified into a strong Category 1 hurricane. However, an increase in wind shear and upwelling of colder waters halted the intensification and Sally weakened slightly on September 15 before turning slowly northeastward. Despite this increase in wind shear, it unexpectedly re-intensified, reaching Category 2 status early on September 16 before making landfall at peak intensity at 09:45 UTC on September 16, near Gulf Shores, Alabama, with maximum sustained winds of 110 mph (180 km/h) and a minimum central pressure of 965 millibars (28.5 inHg).[1][2] The storm rapidly weakened after landfall before transitioning into an extratropical low at 12:00 UTC the next day. Sally's remnants lasted for another day as they moved off the coast of the Southeastern United States before being absorbed into another extratropical storm on September 18.
Numerous watches and warnings were issued in anticipation of the imminent approach of Sally, and several coastline counties and parishes on the Gulf Coast were evacuated. In South Florida, heavy rain led to localized flash flooding while the rest of peninsula saw continuous shower and thunderstorm activity due to the asymmetric structure of Sally. The area between Mobile, Alabama, and Pensacola - Gulf Breeze, Florida took the brunt of the storm with widespread wind damage, storm surge flooding, and over 20 inches (510 mm) of rainfall in the first 24 hours and over 30 inches in 48 hours.[3] Numerous tornadoes also occurred as well. Damage is estimated at $7.3 billion (2020 USD).[4] Sally was the costliest of several destructive 2020 hurricanes whose names were not retired by the World Meteorological Organization following the season, along with Hanna, Isaias, Delta, and Zeta.[5][6]