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The bizarre and destructive 2022 hurricane season ends » Yale Climate Connections


The 2022 Atlantic hurricane season draws to an official close on November 30, after generating 14 named storms, eight hurricanes, two major hurricanes, and an accumulated cyclone energy (ACE) of 95. Those numbers compare with the 1991-2020 averages for an entire season of 14.4 named storms, 7.2 hurricanes, 3.2 major hurricanes, and an ACE index of 123. Thus, the season was near-average for number of named storms and hurricanes, and below average for major hurricanes and ACE index, and it breaks an unprecedented streak of six consecutive years with an above-average ACE index (>126).

One hurricane from 2022 will surely get its name retired: Ian, with over $50 billion in damages and at least 145 deaths, ranking as the fifth-deadliest Atlantic hurricane of the past 60 years. The other major hurricane of 2022 – Hurricane Fiona, which brought major destruction to Puerto Rico and Canada – also has a strong chance of having its name retired.

Figure 1. Preliminary track map for the 2022 Atlantic hurricane season. (Image credit: National Hurricane Center)

Only four hurricanes (all Cat 5s) have made landfall in the contiguous U.S. with stronger winds than Ian. Over the past six years, the U.S. has taken an unprecedented pummeling from category 4 and 5 hurricanes, with seven such landfalls: Harvey (2017 in Texas), Irma (2017 in Florida), Maria (2017 in Puerto Rico), Michael (2018 in Florida), Laura (2020 in Louisiana), Ida (2021 in Louisiana), and Ian (2022 in Florida). The only comparable beating the U.S. has taken occurred from 1945 to 1950, when five category 4 hurricanes hit South Florida (Figure 2).

Figure 2. Tracks of the five Cat 4 hurricanes that hit the U.S. from 1945 to 1950. (Image credit: NOAA)
Figure 3. Tracks of the seven Cat 4 and 5 hurricanes that hit the U.S. from 2017 to 2022. (Image credit: NOAA)

A strangely quiet July, August, and October, but a very active November

The 2022 season was unusually quiet in July and August, with no named storm activity between July 3 and August 31. According to Dr. Phil Klotzbach, this is the first time since 1941 that the Atlantic had no named storm activity between those dates. The unusual quiet was a surprise for a La Niña year, when Atlantic hurricane activity is usually higher than average. October also was quiet, producing only 5 units of ACE – the lowest October ACE since 2009. In contrast, November was unusually active, as Klotzbach documented:

• November had three hurricanes form (Lisa, Martin and Nicole), tying 2022 with 2001 for the most November Atlantic hurricane formations on record.

• Hurricanes Lisa and Martin had maximum sustained winds of 85 mph simultaneously in November – the first time that two hurricanes have had simultaneous maximum sustained winds of 85+ mph in November since 1932.

• Hurricane Lisa made landfall on November 2 in Belize – the first land-falling hurricane in Belize in November since 1942.

• Hurricane Nicole was the latest calendar-year hurricane to make landfall along the east coast of Florida on record.

Hurricane Ian

After rapidly intensifying over the deep, warm waters of the western Caribbean, Hurricane Ian smashed into western Cuba on September 24 as a category 3 hurricane with 125 mph winds. Ian killed five people in Cuba, causing heavy damage and an island-wide blackout.

After crossing Cuba, Ian weakened as it headed toward southwestern Florida. After completing the eyewall replacement cycle, Ian put on another bout of rapid intensification, topping out as a high-end category 4 hurricane with 155 mph winds as it approached landfall. Ian powered ashore along the southwest Florida coast at Cayo Costa Island on September 28 as a category 4 storm with 150 mph winds and a central pressure of 940 mb, tying as the fifth-strongest hurricane on record to make a contiguous U.S. landfall. The mighty hurricane’s winds, storm surge, and flooding rain caused catastrophic damage and knocked out power to more than 2.6 million customers in Florida – approximately 24% of the state’s customers. 

Ian gradually weakened as it moved across Florida at 8 – 9 mph, maintaining hurricane strength about 100 miles inland from the point of its initial landfall. Along its path, Ian dumped record amounts of rain, including more than two feet near New Smyrna Beach and more than a foot in Orlando. The torrential rains triggered multiple flash flood emergencies and record river flooding. Orlando, where weather records extend back to 1892, logged 12.49 inches of rain in 24 hours, smashing its previous 24-hour record of 9.67 inches set on Sept. 15-16, 1945.

After moving offshore the eastern coast of Florida, Ian made a final landfall about 55 miles northeast of Charleston, South Carolina, as a category 1 storm with 85 mph winds. Ian’s storm surge brought major flooding and the third highest water level on record to Myrtle Beach, South Carolina. Ian’s rains led to five indirect deaths in North Carolina and one in Virginia.

Figure 4. Costliest U.S. weather disasters (2022 dollars) from NOAA’s list of billion-dollar weather events.

Ian the 5th-deadliest U.S. hurricane since 1963

The death toll from Hurricane Ian was unusually high for a U.S. hurricane in recent decades. As of November 16, the Florida Medical Examiners Commission identified 139 direct and indirect deaths from Ian in Florida. In addition, North Carolina had five indirect deaths, and Virginia had one, which would put Ian’s U.S. preliminary death toll at 145. NOAA’s list of billion-dollar weather events put Ian’s death toll at 131, a figure subject to future updates. Causes of the direct deaths include drowning in storm surge, storm-driven waves, rip currents, or freshwater flood from rain; falling trees are also a common source of direct deaths. Causes of the indirect deaths include falls during post-storm clean up, traffic accidents, carbon monoxide poisoning from generators, and medical issues compounded by a hurricane.

A direct and indirect death toll of 145 would make Ian the fifth-deadliest U.S. hurricane in the past 60 years, according to statistics of maintained by key federal agencies (Figure 5). The numbers in Figure 5 for hurricanes from 2016 to 2022 are from NOAA’s list of billion-dollar weather events; death tolls from 1963 to 2015 were taken from a 2016 paper, Fatalities in the United States Indirectly Associated With Tropical Cyclones, by Ed Rappaport, former Deputy Director of the National Hurricane Center. He computed direct and indirect deaths using conclusions of medical practitioners wherever possible, and then raw data obtained directly from one or more of the official sources, such as coroners’ offices, emergency managers, and law enforcement officials. The research was unable to find reliable statistics on indirect deaths prior to 1985, so it is possible that earlier hurricanes may have placed higher on the list of deadliest hurricanes – in particular, Betsy (1965), Beulah (1967), and Celia (1970).

Figure 5. Deadliest U.S. hurricanes of the past 60 years, for direct and indirect deaths. Data from 2016 – 2022 is from NOAA’s list of billion-dollar weather events; death tolls from 1963 – 2015 were taken from a 2016 paper, Fatalities in the United States Indirectly Associated With Tropical Cyclones. The number for Ian is preliminary, and will change.

According to a 2010 National Hurricane Center publication and subsequent tropical cyclone final reports, the deadliest Florida hurricane for direct deaths was the 1928 Okeechobee hurricane, which killed at least 2,500; the second-deadliest was the catastrophic category 5 1935 Labor Day hurricane, which killed 408 people. NHC has not yet released the number of direct deaths for Ian, but the analysis done by NBC (see Tweet below) found 64 drowning deaths in Florida. If these deaths are deemed to be direct deaths, Ian would rank as the deadliest Florida hurricane since 1935, and the eighth-deadliest U.S. hurricane of the past 60 years for direct deaths.

Why so many deaths from Ian?

The primary reason for Ian’s high death toll is straightforward: A large number of people in a vulnerable location being hit by a strong hurricane, increasing the risk of deaths. The amount of risky development that has occurred in southwest Florida – near sea level, on barrier islands, and on former wetlands – was a disaster waiting to happen, and it happened. Cape Coral, where some of Ian’s deaths were reported, was a particularly vulnerable location, because of unwise building practices.

This highly vulnerable population had the added hazard of having to interpret a difficult forecast situation, since the steering currents for Ian were relatively weak. Ian was approaching the coast at an oblique angle, so small changes in the hurricane’s projected track made a large difference in where the storm would hit. Ian’s eventual landfall was near the edge of the cone of uncertainty 48-72 hours before landfall. The error in the official NHC track forecast was near average for forecasts of 24 – 48 hours for Ian, and 15 – 30% more than average for forecasts of 96 – 120 hours (Figure 6). The errors in the official NHC intensity forecasts were greater than average (Figure 7), but they were better than one would expect for a hurricane that underwent two bouts of rapid intensification.

Figure 6. Track forecast errors for Hurricane Ian. The black line is the official NHC forecast, and the colored lines are from the top hurricane forecasting models. Data is from Brian Tang, SUNY Albany.
Figure 7. Intensity forecast errors for Hurricane Ian. The black line is the official NHC forecast, and the colored lines are from the top hurricane forecasting models. Data is from Brian Tang, SUNY Albany.

NHC made good forecasts in a difficult situation, and continually called attention to the greater-than-usual forecast uncertainty. A storm surge watch was posted for the entire southwest coast of Florida all the way to the Everglades, including Ian’s eventual landfall location and the Naples area, at 11 p.m. Sunday, advising of a storm surge of 4 – 7 feet in and around the Fort Myers area. This watch was upgraded to a storm surge warning from Tampa south to the Everglades at 5 p.m. Monday, 46 hours before Ian’s 3 p.m. Wednesday landfall. Unfortunately, Lee County, where 62 of Ian’s deaths occurred, did not issue an evacuation order in time. As documented in the Tweet above, “Lee County’s emergency management website says it can take 41 hours to evacuate people; Ian made landfall about 32 hours after the first evacuation order.”

Hurricane Fiona

After bringing torrential rains to the Leeward Islands which killed one person in Guadeloupe, Hurricane Fiona hit southwestern Puerto Rico on September 17 as a category 1 storm with 85 mph winds. Fiona is being blamed for 25 deaths on the island, and more than $5 billion in damage to Puerto Rico’s public infrastructure, with additional billions of dollars in damage to private property. The hurricane caused an island-wide power outage and the loss of water service to about 25% of the island; ten days after the hurricane hit, more than a third of Puerto Rico’s customers were still without power. Fiona dumped 31.34 inches of rain at Ponce, Puerto Rico, and a gauge at Rio Cerrillos recorded 27.14 inches in 24 hours, setting an all-time 24-hour precipitation record for Puerto Rico. Heavy rains from Fiona also affected the Dominican Republic, where two people died.

Fiona intensified into a category 4 hurricane with 130 mph winds as it headed north toward Canada. A few hours after losing its tropical characteristics, a weakening Fiona became a hurricane-strength extratropical storm, hitting eastern Nova Scotia, Canada, on September 24 with sustained winds of 90 mph and a central pressure of 931.6 mb. This reading smashed the nation’s previous all-time record for central pressure in any storm, tropical or non-tropical, of 940.2 mb (January 20, 1977). 

With insured damages of $495 million (USD), Fiona was the costliest storm on record for Atlantic Canada. The previous record was $320 million (2022 USD) from Hurricane Juan of 2003, which made landfall near Halifax, Nova Scotia, at category 2 strength with 100-mph sustained winds.

Hurricane Nicole

The final land-falling hurricane of 2022 was Hurricane Nicole, which made landfall in the Bahamas as a tropical storm on November 9 before hitting Vero Beach, Florida, on November 10 as a category 1 hurricane with 75 mph winds and a central pressure of 981 mb. Nicole was the first November hurricane to hit Florida from the east since 1935. Nicole is being blamed for five deaths in Florida and at least $522 million in damage to Volusia County. Nicole’s storm surge, occurring on top of king tides, brought the highest water level on record to Jacksonville, Florida. As of November 18, 16 condos and commercial buildings on the Florida coast were still deemed unsafe because erosion from Nicole’s storm surge undermined the buildings.

Tropical Storm Colin

The other named storm to hit the U.S. in 2022 was Tropical Storm Colin, which was named when the storm’s center was inland, about 10 miles northeast of Charleston, South Carolina, on June 5. Colin lasted just over a day as a minimal-strength tropical storm, as it tracked northeastward into North Carolina. No major damage was reported, but Colin was responsible for one death – a drowning in a rip current off the coast of North Carolina. (One could argue that Colin did not count as a landfall, since it wasn’t named until it was centered over land, but NHC may change this assessment in post-analysis.)

The 1950 – 2020 average for contiguous U.S. landfalls is three named storms, with one being a hurricane, according to tropicalstormrisk.com. The two-year period 2020 – 2021 had a truly astonishing and record-breaking 19 landfalls in the contiguous U.S., six times the average for a two-year period, so 2022 was a welcome respite in this regard, particularly for the U.S. Gulf Coast, which suffered greatly in 2020 – 2021. However, the lack of rainfall from land-falling tropical cyclones along the Gulf Coast contributed to record low water levels on the Mississippi River this fall, which has cost billions of dollars by inhibiting barge traffic.

Two rapid intensifiers in 2022

Two out of eight of this year’s Atlantic hurricanes intensified by at least 35 mph in 24 hours – the official National Hurricane Center definition of rapid intensification. This is a lower proportion of rapidly intensifying hurricanes than has been observed in recent years:

Ian: 40 mph ending at 6Z Sep. 27, and 40 mph ending at 12Z Sep. 28; and
Danielle: 35 mph ending at 12Z Sep. 2.

Figure 8. Number of named Atlantic storms lasting two days or less, 1968-2022. The trend (blue line) is decidedly upwards.

Four short-lived storms in 2022

Four of this year’s storms were “shorties” – named storms that lasted two days or less (Alex, Bonnie, Colin, and Hermine). As explained in a post here last year, improved technology has allowed the identification of weak, short-lived tropical cyclones that would have escaped detection in previous years. No link between warming of the oceans from increased greenhouse gases and the observed increase in the number of Atlantic named storms has been firmly established. According to the 2021 Sixth Assessment Report from the Intergovernmental Panel on Climate Change, the global frequency of tropical cyclones will likely hold steady or decrease as global warming continues. Among those tropical cyclones, though, the proportion that reach Category 4 or 5 will very likely increase.

Bob Henson contributed to this post.

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