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What made Hurricane Ian so intense: By the numbers

Ian tied for the fifth-strongest hurricane to make landfall in the United States, causing destruction probably among the worst recorded

Tammy Drake and her daughter Maddy Drake evacuate Fort Myers Beach, Fla., on Friday amid damage from Hurricane Ian. (Ted Richardson for The Washington Post)
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Hurricane Ian will be remembered as one of the most consequential in recent U.S. history, leaving scores of homes and businesses obliterated in addition to a still-rising number of deaths.

After pummeling Cuba, the storm came ashore on the western coast of Florida with an unforgiving storm surge that gutted the first floors of buildings and winds that knocked out about a quarter of Florida’s power. The Category 4 storm dropped more than 20 inches of rain on central parts of the state.

That wasn’t the end of Ian. It meandered over water again and made landfall in South Carolina as a Category 1 hurricane.

See Hurricane Ian’s damage across Florida in photos, videos and maps

President Biden said the scale of Ian’s devastation will probably rank among the “worst in the nation’s history.” Below are key figures on the storm’s impact and strength.

Storm impacts

89 deaths and counting — Most of the deaths reported so far have been drownings in Florida, according to the Florida Medical Examiners Commission. County sheriffs have reported higher fatality figures, and the official toll is expected to rise.

The highest number of deaths happened near the storm’s landfall in Lee County, which includes Fort Myers Beach and Sanibel Island. The deadliest hurricane on record in Florida killed at least 2,500 people in 1928. Hurricanes in 1919, 1926 and 1935 each claimed between 350 and 800 lives, although all these numbers are considered somewhat unreliable.

Deaths from Ian have also been reported in North Carolina and Cuba.

6,000-plus flights canceledRoughly 2,000 flights were canceled each day Wednesday through Friday, primarily in zones between where Ian made landfall in Florida and South Carolina. Airports in Tampa and Orlando, among others in Florida, completely shut down as the storm passed. Charleston International Airport in South Carolina also closed. Most other airports in that area remained operational but with significant delays and cancellations.

2.5 million evacuation orders — Millions of Floridians were placed under evacuation orders as Ian approached. Florida Gov. Ron DeSantis (R) said about 100 evacuation centers opened statewide. Many people did not evacuate, however.

The evacuation orders covered many fewer people compared with those for Hurricane Irma, which made landfall on the Florida peninsula as a Category 3 storm in 2017. Irma was responsible for the largest U.S. evacuation in history, with roughly 7 million people ordered to leave their homes, mostly in Florida.

Photos: Striking before and after photographs over Hurricane Ian’s path

3.4 million-plus U.S. power outages — Around 2.7 million customers were in the dark at peak outage in Florida. That adds up to about 25 percent of the state, markedly higher than for Category 5 Hurricane Michael, which left 4 percent of the state without power in 2018. North Carolina recorded around 350,000 people without power at its peak, and South Carolina had around 218,000. Virginia topped 100,000. Georgia added about 15,000 out at peak.

However, the U.S. power outages pale in comparison with those in Cuba, where failures after Ian caused the whole island of 11 million to go dark.

$60 billion-plus in insured losses — Ian is estimated to have caused more than $60 billion in private insured losses just in Florida, making it the second-largest disaster loss event on record, according to the industry trade group Insurance Information Institute. Ian trails Hurricane Katrina of 2005, which caused $89.7 billion in inflation-adjusted insured losses.

Storm statistics

Three landfalls — Ian made landfall as a hurricane three times. It first came ashore as a 125-mph Category 3 storm near La Coloma, Cuba, early on Sept. 27. On the afternoon of Sept. 28, the storm struck Cayo Costa, Fla., as a Category 4 with 150-mph winds. Two days later, Ian made its final landfall near Georgetown, S.C., as a Category 1 at 85 mph.

Fifth-strongest winds — At 150 mph, Ian’s landfall wind speed in Florida ties for the fifth-strongest on record in the United States, a mark shared by seven other storms. It ties for the fourth-highest landfall speed on record in Florida. The highest winds are rarely recorded, given a relatively sparse observation network, but observations show impressive gusts across Florida at 140 mph in Cape Coral, 135 mph in Punta Gorda and Solana, 112 mph in Pelican Bay and 110 mph in La Belle. Places as far from landfall as Tampa and Daytona saw hurricane-force wind gusts.

Gusts of 92 mph and 94 mph were also recorded at Shutes Folly, S.C., and Chesapeake Light Tower, Va., respectively.

Sixth major hurricane to hit the Gulf in the last six years — Over the past six seasons, six hurricanes at Category 4 or higher have hit the continental United States: Harvey and Irma (2017), Michael (2018), Laura (2020), Ida (2021) and Ian (2022).

Other areas nearby have also been hit hard, notably portions of the Caribbean. Puerto Rico was hit by Category 4 Maria in 2017, and Category 5 Irma trashed numerous islands before reaching the United States. Dorian also roared through the Bahamas as a Category 5 before crawling northward off the Southeast coast. Hurricanes Eta and Iota in 2020 hit Nicaragua as a Category 4 as well.

All of these storms experienced rapid intensification, increasing their wind speeds by at least 35 mph within 24 hours. Scientists expect that rapid intensification events, especially in strong storms, will increase due to warming ocean waters associated with climate change.

12-foot-plus storm surge — A surge, or rise in ocean water above normally dry land at the coast, as high 12 feet was reported by DeSantis shortly after landfall in Florida on Wednesday afternoon, and forecast values of 12 to 18 feet are suspected to have occurred in some spots. The Weather Channel’s hurricane expert Rick Knabb indicated some areas were likely above 12 feet, “but it takes time to collect water marks.” Tide gauges in Naples and Fort Myers posted their highest water levels on record.

Imagery of houses underwater up to near the ceiling would indicate at least 8 to 10 feet of surge. Values were almost certainly higher in parts of the Florida coast, which will be determined in ongoing surveys. A surge around 5 feet was also reported near Myrtle Beach, S.C., its third-highest on record, as Ian made its second U.S. landfall nearby.

21.16 inches of rain — Union Park, just northeast of Orlando in central Florida, picked up 21.16 inches of rain from the storm. That’s almost four times the average rainfall for September in Orlando, and it fell in about 36 hours. The rainfall from Ian pushed Orlando to its wettest month on record. Another dozen official observation sites topped 10 inches from the storm. Parts of the region saw a “1 in 500 year” rainfall (meaning it had only a 0.2 percent chance of happening in a given year), leading to widespread and significant flooding of lakes and rivers.

Ian’s rainfall output in Florida on Thursday ranked as the third-most on record since 2005, according to the National Weather Service, trailing only two exceptionally rainy days during Hurricane Harvey.

Charleston picked up 10.75 inches from Ian, which was the most outside Florida.

940 millibars landfall pressure The strength of a hurricane’s winds is linked to the how low the atmospheric pressure is at the storm’s center; pressure lower than 980 millibars is typically thought of as conducive for hurricane formation. Ian rapidly strengthened from a tropical storm to a Category 3 hurricane with a 952-millibar pressure as it struck Cuba. This probably helped the core of the hurricane exit the country in a healthy condition, setting up a second round of rapid intensification that allowed for a 937-millibar minimum pressure.

The 937-millibar landfall pressure was the ninth-deepest central pressure for a storm hitting Florida, behind events such as Category 5 storms Michael in 2018 (919 millibars) and Andrew in 1992 (922 millibars).

Thousands of lightning strikes — In the time just before landfall, as many as 1,000 lightning events were detected in the eyewall — making it one of the most electric eyewalls in a storm in the Gulf of Mexico. Overall, as many as 34,000 lightning events were recorded in the storm, according to scientists with Vaisala, a company that operates a national lightning network. That places it in the high end of tropical cyclones for lightning. While the mechanisms behind intense eyewall lightning are not fully understood, it tends to favor atypically powerful storms.

Two — There are two months left of this hurricane season, which runs June 1 through Nov. 30. October in particular can deliver high-end storms, so it’s not time to stop watching just yet.