Hurricane Ian Rapidly Intensifies to Cat. 4

Hurricane Ian rapidly intensified to Category 4 on the Saffir-Simpson Scale as it approached the coast of Southwest Florida early on Wednesday. At 8:00 a.m. EDT on Wednesday the center of Hurricane Ian was located at latitude 26.0°N and longitude 82.7°W which put it about 60 miles (95 km) southwest of Punta Gorda, Florida. Ian was moving toward the north-northeast at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h). The minimum surface pressure was 937 mb.

A Hurricane Warning was in effect for the portion of the coast from Chokoloskee to Anclote River, Florida. The Hurricane Warning included Tampa Bay. Tropical Storm Warnings were in effect for all of the Florida Keys. A Tropical Storm Warning was in effect for the portion of the coast from Flamingo to Chokoloskee, Florida. A Tropical Storm Warning was in effect for Lake Okeechobee. A Tropcial Storm Warning was in effect for the portion of the coast from Anclote River to Indian Pass, Florida. A Tropical Storm Warning was in effect for the portion of the coast from Flamingo, Florida to South Santee River, South Carolina. Tropical Storm Warnings were also in effect for the Cuban provinces of La Habana, Mayabeque and Matanzas. Tropical Storm Warnings were in effect for Bimini and Grand Bahama Island.

Hurricane Ian completed a quick eyewall replacement cycle during Tuesday night. The original eye and eyewall quickly dissipated and a new larger eye was evident on satellite and radar images. A circular eye with a diameter of 30 miles (50 km) is now present at the center of Ian’s circulation. The new eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms. Bands of showers and thunderstorms are revolving around the core of Hurricane Ian’s circulation. Storms near the core are generating strong upper level divergence that is pumping mass away to the north and east of the hurricane.

The quick eyewall replacement cycle caused the circulation around Ian to get bigger. Winds to hurricane force extended out 40 miles (65 km) from the center of Ian’s circulation. Winds to tropical storm force extended out 175 miles (280 km) from the center of circulation. The Hurricane Intensity Index (HII) was 33.3. The Hurricane Size Index (HSI) was 16.5 and the Hurricane Wind Intensity Size Index (HWISI) was 49.6. Hurricane Ian was capable of causing regional severe damage.

Hurricane Ian is now stronger than Hurricane Charley was when Charley made landfall in Southwest Florida in 2004, and Ian is much bigger than Charley was. Hurricane Ian is very similar in size and intensity to Hurricane Michael, when Michael hit Northwest Florida in 2018.

Ian will move through an environment favorable for a powerful hurricane during the next few hours. Ian will move over water where the Sea Surface Temperatures are near 29˚C. An upper level trough over the eastern U.S. will produce southwesterly winds that will blow toward the top of Ian’s circulation. Those winds will cause vertical wind shear. The wind shear is not likely to be strong enough during the next few hours to cause Hurricane Ian to weaken significantly before it makes landfall in Southwest Florida.

The upper level trough over the eastern U.S. will steer Hurricane Ian toward the north-northeast on Wednesday. On its anticipated track the center of Hurricane Ian could make landfall on the coast of Southwest Florida between Ft. Myers and Sarasota on Wednesday afternoon. Ian could move slowly inland over Central Florida on Thursday. Hurricane Ian is likely to bring a prolonged period of strong gusty winds to Southwest Florida and to Central Florida. Ian will be capable of causing severe damage. A prolonged period of strong winds could cause widespread electricity outages. Hurricane Ian will move slowly inland and 10 to 20 inches of rain could fall in some locations. Fresh water flooding could occur in Central Florida. A storm surge of 12 to 16 feet (3.5 to 5 meters) could occur along the coast of Southwest Florida.

Hurricane Ian is bigger and stronger than Hurricane Charley was when Charley hit Southwest Florida in 2004. Ian is likely to cause much more wind damage than Charley caused. Hurricane Ian is also likely to cause a higher storm surge along the coast than Charley caused.