2024 Year in Review: Billion Dollar Tropical Systems

Four hurricanes broke the banks this year, each with heavy impacts on life at their landfall and beyond. These tropical cyclones were Beryl, Debby, Helene, and Milton. 

Hurricane Beryl Breaks Early Season Records from Tropics to Canada 

Beryl developed in the eastern Atlantic Ocean on June 28th and strengthened rapidly as it moved westwards, causing extensive damage on the island of Grenada as a Category 4 hurricane on July 1st. It became the earliest Category 5 Hurricane ever in the Atlantic Basin on July 2nd. Beryl then weakened a bit on its long trek across the Caribbean, making landfall in the Yucatan Peninsula on July 5th. Beryl’s move across northeastern Mexico caused it to weaken further to a tropical storm, which then moved into the Gulf of Mexico on July 6th. However, Beryl slowly gained strength agained as it curved across the western Gulf, and became a Category 1 Hurricane as it approached the Texas coast. 

As Beryl moved across the Gulf of Mexico, initial forecasts suggested a landfall in South Texas. As the storm headed towards Texas, the track shifted slightly eastwards, with the center of Hurricane Beryl making landfall near Matagorda, Texas, in the early morning hours of July 8th. The center of Beryl passed about 25 miles west of Houston, with the strongest part of the eyewall passing directly over Houston. Widespread wind gusts to near 80 mph caused devastating damage to the power grid, with several million households losing power in Texas. Heavy rain and a storm surge of 4 to 6 feet caused flooding as well. Over 40 deaths were reported in the United States, mostly in Texas. The Lone Star State suffered several billion dollars of storm damage, and the total damage across the United States was over $7 billion (about $22 per person in the U.S.). 

As Beryl moved inland, it was slow to weaken, causing impacts across many states. Beryl spawned 68 tornadoes from July 8th to July 10th, leaving a trail of damage from Texas, Louisiana, and Arkansas north to Kentucky and Indiana, eventually reaching western New York State. Fierce winds and heavy rain impacted much of eastern Texas and extended into Arkansas and Louisiana, leading to widespread power outages. Flooding rains reached as far as Vermont, New Hampshire, and parts of Canada. 
 

Hurricane Debby Tracks from the Caribbean to Canada in Early August 

As July ended, a weather disturbance moved from the northeast Caribbean across Puerto Rico and Hispaniola. This system brought heavy rain to Cuba at August's opening and became a tropical depression on the evening of August 2nd. It strengthened into Tropical Storm Debby on the afternoon of August 3rd as it moved past Cuba into the Gulf of Mexico, and the storm's outer bands began to impact southwest Florida. 

Debby continued to strengthen, bringing torrential rainfall totals of 15 to 20 inches in the Sarasota-Bradenton area (Manatee and Sarasota counties) on August 4th. This touched off widespread flash flooding, causing closed roads and requiring water rescues. Debby became a hurricane on the evening of August 4th, as the eye passed about 85 miles west of Tampa Bay. The outer bands brought wind gusts of 60 mph to the Clearwater-St. Petersburg area, and rain amounts of 8 to 12 inches. Hurricane Debby made landfall on August 5th near Steinhatchee in northwest Florida with sustained winds of 80 mph, throwing another narrow band of 12 to 17 inches of rain over Florida's Big Bend. A peak storm surge of 4.65 feet was recorded at Cedar Key, and at least four fatalities associated with Debby occurred in Florida. 

Debby weakened to a tropical storm as it moved across southeast Georgia and into the Atlantic Ocean. Debby strengthened slightly as it looped towards the northwest, and made a second landfall near Bulls Bay, S.C., as a tropical storm on August 8th. Widespread heavy rain of 12 to 22 inches occurred from eastern Georgia, across coastal South Carolina, and up into the Cape Fear area of North Carolina. As the system moved northwards, seven tornadoes were reported in South Carolina, and ten tornadoes hit North Carolina. Additionally, three tornadoes spawned in Virginia, while West Virginia, Delaware, Pennsylvania, and New York each also reported a tornado. 

Total damage estimates in the United States reached over $2 billion (about $6.2 per person in the U.S.), and ten total lives were lost. The remnants of Debby brought heavy rain to eastern Canada, with a single-day rain record set in Montreal at 6.10 inches of rain. Widespread flooding caused damage through many parts of eastern Canada. 
 

Hurricane Helene Devastates Florida through Southern Appalachia 

A summer-season area of low pressure, called the Central American Gyre, combined with other very favorable conditions to lay the groundwork for what would brew into a catastrophic hurricane. On September 24th, Tropical Storm Helene formed east of Nicaragua in the western Caribbean. Helene intensified into a hurricane the day after as it squeezed northward through the Yucatan Channel into the Gulf of Mexico. Helene then intensified rapidly on September 26th as it moved over very warm waters of the Gulf of Mexico Loop Current. The hurricane tracked north-northwest towards Florida's Big Bend, where it would later come ashore. Helene's peak intensity was recorded at landfall, near Perry, Fla., as a Major Category 4 hurricane, reaching 140 mph sustained winds and holding a minimum central pressure of 938 mb. It was the strongest hurricane to ever make landfall in the Big Bend region. Helene then smashed through Georgia as a hurricane, tore into the western Carolinas as a tropical storm, and then moved into southwestern Virginia and Tennessee before stalling until it dissipated on September 28th. Its remnants continued to deluge areas from Kentucky into the Northeast. 

Unofficially, Hurricane Helene is currently the 3rd costliest hurricane in the U.S. history, approaching Hurricane Harvey at an estimate of up to $120 billion (about $370 per person in the US) in damages. Before even making landfall, Helene caused a record-breaking storm surge to wreak havoc along Florida's Gulf Coast from the Greater Tampa Bay Region, largely exceeding 5 to 9 feet, through the Big Bend, which saw surges exceed 15 feet locally. The worst of Helene's associated flooding and damage was from record rainfall, devastating southeastern Appalachia. The region was influenced heavily by a predecessor rainfall event, where a low-pressure trough that helped steer Helene and its tropical moisture soaked the ground and subsequently left the region extremely vulnerable. By the end of the storm, rainfall totals unheard of in the region were tallied. Widespread five-day accumulations of 4 to 10 inches were marked from Florida's Big Bend into Kentucky, with a surplus of 10 inches in portions of western South Carolina into far southwest Virginia, and catastrophic totals surpassing 20 inches marked for much of western North Carolina. The French Broad and Swannanoa Rivers of Asheville, N.C., smashed their previous record heights by feet, and many other creeks flowed over to virtually destroy less fortunate towns and homes. This deluge caused over 2000 landslides to be tallied, with 260 posing an imminent threat or damaging homes and over 1,000 that impacted roads, rivers, and structures. Many of these landslides were quick-moving debris flows of mud, rock, structural debris, and water that left residents with little to no warning of danger ahead of their impact. Portions of I-26 and I-40, along with the Blue Ridge Parkway, saw landslides close roadways until further notice, isolating the region and heavily delaying outside aid. 

On top of catastrophic flooding, heavy shifting winds toppled trees and downed the power of over 4 million homes and businesses, and 35 tornadoes from Georgia through Virginia were spun up by Helene. When all threats were said and done, 234 fatalities and 26 people that remain missing are attributed to the record-breaking storm. 
 

Hurricane Milton Destroys Recovery Efforts in Florida 

Just two weeks after Helene inundated beaches across the coast of Florida’s western peninsula with record storm surge heights, Hurricane Milton would cause heavy damage through much of the Sunshine State. Milton was also birthed from a disturbance in the Central American Gyre, much like Helene, but this disturbance crossed northwestward over the Yucatan Peninsula before organizing in the Gulf of Mexico and being named Tropical Storm Milton on October 5th. Milton then took a sharp eastward turn toward Florida from the Bay of Campeche, a track seen only three times before in the recorded history of hurricanes. Aligning with this track through landfall, Milton achieved hurricane status on October 6th. The very next day, Milton underwent explosive strengthening, intensifying from a Category 1 Hurricane into a fierce Major Category 5, enabled by severely high ocean heat and a calm environment. Milton’s central pressure, at its lowest, was 897 mb with 180 mph sustained winds, becoming the 5th strongest hurricane ever recorded in the Atlantic Basin and the 2nd strongest hurricane ever recorded in the Gulf of Mexico, just behind 2005’s Hurricane Rita. Milton took a northeastward turn as a low-pressure trough directed it into Florida. Although weakened by an agitated environment, Milton struck south of Tampa Bay near Siesta Key, Fla. as a Major Category 3 hurricane on the night of October 9th, holding 120 mph sustained winds and a central pressure of 954 mb. Overnight, Milton rapidly swept across the Florida Peninsula and then moved into the Atlantic and lost its hurricane status on the afternoon of October 10th. 

Milton was initially forecasted to bring even more devastating effects to the Tampa Bay area with a forecasted track just north of the bay, but luckily, this forecast did not verify to bring even more record-breaking storm surge. Despite this, Milton still managed to accrue a disastrous estimate of up to $85 billion (about $260 per person in the U.S.) in U.S. damages. Milton spawned a total of 38 tornadoes through Florida along its outer bands, with nine EF2+ rated twisters and a localized tornado outbreak through St. Lucie County. Flooding from Milton’s rainfall, which reached up to 18 inches in St. Petersburg, Fla., left several rivers to flood downstream, as soil already saturated from Helene left rain to run off sluggishly across flat terrain. Storm surges of 5 to 8 feet were widespread in the Tampa Bay area, and over two million homes and businesses saw power outages. All these factors hit heavily upon structures already left vulnerable by Helene. Overall, the crushing blow to Florida that Milton dealt to Florida caused 32 deaths. 

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Image: Satellite Image of Hurricane Beryl (NOAA AOML Research)