Tropical Storm Claudette was a weak tropical cyclone that caused heavy rain and tornadoes across the Southeastern United States in June 2021, leading to severe damage. The third named storm of the 2021 Atlantic hurricane season, Claudette originated from a broad trough of low pressure over the Bay of Campeche on June 12. The disturbance moved erratically over the region for the next several days, before proceeding northward with little development due to unfavorable upper-level winds and land interaction. Despite this, the National Hurricane Center (NHC) initiated advisories on it as a Potential Tropical Cyclone late on June 17, due to its imminent threat to land. The disturbance finally organized into Tropical Storm Claudette at 00:00 UTC on June 19 just before landfall in southeast Louisiana. Claudette weakened to a depression as it turned east-northeastward before moving through Mississippi, Alabama, Georgia, and South Carolina. Baroclinic forcing then caused Claudette to reintensify into a tropical storm over North Carolina early on June 21 before it accelerated into the Atlantic Ocean later that day. Soon afterward, it degenerated into a low-pressure trough on the same day, before being absorbed into another extratropical cyclone on the next day.
Claudette produced gusty winds, flash flooding, and tornadoes across much of the Southeastern United States. Claudette overall caused minor impacts along the Gulf of Campeche's coastline due to the system stalling in the region as an Invest and a Potential Tropical Cyclone. Impacts were most severe in Alabama and Mississippi, where heavy rains caused flash flooding. Several tornadoes in the states also caused severe damage, including an EF2 tornado that damaged a school and destroyed parts of a mobile home park in East Brewton, Alabama, injuring 20 people. A total of 14 people died in Alabama due to the storm, including 10 from car accidents. Monetary losses across the United States is estimated to be at $375 million.
Meteorological history
On June 6, a tropical wave entered the Caribbean Sea. The wave briefly became convectively active before moving inland over Nicaragua and Honduras on June 10. The remnants of the system began to interact with the eastern portion of an enhanced monsoon trough in the Eastern Pacific and at 12:00 UTC on June 11, the National Hurricane Center noted the possibility of a trough of low pressure to develop in the upcoming few days over the Bay of Campeche and southwestern Gulf of Mexico. The large disturbance then moved out of the Eastern Pacific into Mexico and 24 hours later, a cluster of convection formed over the Bay of Campeche and parts of Mexico and Central America. Moving erratically over the bight, the system split into two disturbances on either side of Central America, with the southern portion becoming Tropical Storm Dolores. The northern disturbance gained a broad circulation on June 13 and developed an area of low pressure on June 14. After meandering in the Southern Gulf of Mexico for a couple of days, the sprawling, disorganized low began to move north-northeastward. Over the next few days, the structure of the system changed minimally due to unfavorable upper-level winds and land interaction, although convective activity occurred continuously. Organization began to steadily increase east of the circulation, but a Hurricane Hunters reconnaissance aircraft investigated the system on June 17 and did not find a closed surface circulation. However, due to its imminent threat to land, the NHC designated the disturbance as Potential Tropical Cyclone Three at 21:00 UTC that day, and started issuing advisories on it. This designation is given to tropical disturbances that have not acquired tropical cyclone status, but are likely to bring tropical storm-force or higher winds to an area, in this case the Gulf Coast of the United States, and was first used for the precursor to Tropical Storm Bret in 2017. Around this time, convection was increasing and a broad curved banding feature developed on the eastern side of the storm, with the NHC describing its structure more resembled that of a subtropical cyclone. Hurricane Hunters data indicated that the system was rather lopsided, with convective activity being displaced east of the ill-defined center of circulation. This was due to wind shear produced by an upper-level trough over the western shore of the Gulf of Mexico.
The next day, the center reformed further north, which increased convection and adding a curvature to the lower-level clouds. A hurricane hunter flight later that day confirmed the circulation had become well-defined and at 00:00 UTC on June 19, the system became a tropical storm as it already had gale-force wind. The storm had some characteristics of a subtropical storm, but was classified as sheared tropical storm since the upper-level trough responsible for its appearance was over Texas and not the storm itself. The system reached its peak intensity with winds of and a pressure of as it made landfall in Terrebonne Parish, Louisiana 25 nm south-southwest of Houma at 04:30 UTC. Operationally, the system was not upgraded to a tropical storm until 09:00 UTC, receiving the name Claudette, by which time it was already inland over southeastern Louisiana and weakening. Turning northeastward, Claudette moved into Southeastern Mississippi and weakened to a depression at 18:00 UTC. After crossing the state line into Alabama, Claudette gradually turned east-northeastward and moved through North Georgia into Upstate South Carolina as a tropical depression. Deep convection increased in curved bands late on June 20, but the center was not well defined. At 06:00 UTC on June 21 however, Claudette restrengthened into a tropical storm while still located over southeastern North Carolina as more organized rainbands formed along and just off the coast. Sustained winds at the time once again reached , although its pressure was slightly higher this time. Claudette emerged over the Western Atlantic Ocean later that day as a tropical storm while embedded within a larger low pressure envelope accelerating to east-northeast, as it began its extratropical transition. After moving into the Atlantic Ocean, Claudette moved alongside the coast of the United States and became an extratropical low at 06:00 UTC on June 22. The low continued to move northeastward, before dissipating about 100 nm southeast of the coast of Nova Scotia as it was absorbed into another extratropical storm to the west.
Preparations
At 21:00 UTC on June 17, a Tropical Storm Warning was issued from Intracoastal City, Louisiana to the Alabama-Florida state line, including the New Orleans Metropolitan Area, Lake Pontchartrain, and Lake Maurepas, upon designation as a potential tropical cyclone. The warning between Morgan City and Intracoastal City was later cancelled at 15:00 UTC on June 18.Flash Flood Watches were also ordered for much of Southeast Louisiana and Mississippi between June 18–20, and also for central and southern Alabama. Coastal flood warnings were also posted from Intracoastal City to the Mississippi-Alabama state line. In anticipation of Claudette, the Storm Prediction Center issued multiple Tornado Watches for southern Louisiana and Alabama, the Florida Panhandle and Georgia as conditions appeared favorable for tornadogenesis and embedded supercells were expected to form in the outer bands of the storm. Louisiana Governor John Bel Edwards issued a state of emergency for the state on June 17, banning price gouging and allowing the distribution of state-provided emergency relief. Sandbag sites were opened in many parishes across Southeast Louisiana. The Chevron Corporation and Occidental Petroleum removed non-essential staff and implemented severe weather protocols on their Gulf of Mexico facilities, some of which are located roughly offshore Louisiana.
At least 90,000 sandbags were sent to coastal areas in Mississippi by the state emergency management agency, who advised residents to remain vigilant. Several events, including Juneteenth events were cancelled or postponed due to the threat of Three in southern Mississippi, 2021 was the first year Juneteenth was officially a federal holiday. The De Soto National Forest shut down recreation sites near Saucier and river landings along Black Creek. In neighboring Alabama, construction crews had to hastily finish repairs on bulkheads in Fairhope and drainage in Downtown Mobile, the former of which was damaged by Hurricanes Sally and Zeta from the previous year. The Gulf Islands National Seashore in Florida closed down Fort Pickens, issuing a mandatory evacuation for all staff and visitors of the reserve which lasted until noon on June 18. This was due to concerns of high tides pushing sand onto Fort Pickens Road, creating hostile conditions for usage. Despite this, "Opal Beach", the landfall site of Hurricane Opal, and Perdido Key remained open. A total of 5–15 inches of rainfall was forecasted by the NHC on June 19 as Claudette moseyed eastward along the deep south.
At 15:00 UTC on June 19, a Tropical Storm Watch was issued for North Carolina from Cape Fear to Duck. By 09:00 UTC the next day, a Tropical Storm Warning had been ordered from Little River Inlet, South Carolina to Duck. A Tropical Storm Watch also extended from Little River Inlet to the South Santee River in South Carolina. Storm surge of up to 1–3 feet was possible from the North Carolina-Virginia border south to Little River Inlet. Heavy rain and even the potential for isolated tornadoes remained.
Impact and aftermath
Mexico and Central America
The Central American Gyre that later spawned Tropical Storms Claudette and Dolores caused torrential rainfall in parts of Central America and Mexico. Flooding began as early as June 11 and continued for nearly a week. Rainfall was particularly intense across Veracruz, Oaxaca, and Puebla. Thirty-three municipalities in Veracruz saw significant effects, with thirteen reporting damage; at least 402 homes were damaged by flooding and landslides across the affected areas. The Isla municipality saw the most damage with 192 homes affected. Several rivers overtopped their banks, inundating surrounding communities. The overflowing Pintores River in Coatepec inundated 105 homes. Sinkholes occurred the city of Veracruz, Cosamaloapan between the Gloria de Coapa and Poblado Dos communities, and in Misantla. The Secretariat of National Defense (SEDNA) deployed personnel in Xalapa to assist in cleanup efforts.
Eight municipalities in Puebla saw minimal damage from the storm, primarily limited to minor flooding and blocked roads. A landslide within the Sierra Norte de Puebla briefly isolated the communities of San Agustín Altiuacan and Tlapehuala. The swollen Balsas River (locally referred to as the Atoyac River) threatened multiple bridges and submerged some homes in the Reforma Sur neighborhood. The Secretary of Civil Protection and Comprehensive Risk Management provided 24 mats and 85 blankets to affected residents in that community. A localized flood in the city of Puebla affected the Museo de la Música Mexicana, the Museo Casa del Títere, and the Casa de la Música de Viena; water reached a depth of .