Hurricane Catarina, or Cyclone Catarina () was the only recorded hurricane-strength South Atlantic tropical cyclone. Catarina made landfall in the South Region of Brazil at peak intensity as a Category 2- equivalent tropical cyclone on 28 March 2004.

The storm developed out of a stationary cold-core upper-level trough on 12 March. Almost a week later, on 19 March, a disturbance developed along the trough and traveled towards the west-southwest until 22 March when a ridge stopped the forward motion of the disturbance. The disturbance was in an unusually favorable environment with slightly below-average wind shear and above-average sea surface temperatures. The combination of the two led to a slow transition from an extratropical cyclone to a subtropical cyclone by 24 March. The storm continued to obtain tropical characteristics and became a tropical storm the next day while the winds steadily increased. The storm attained wind speeds of —equivalent to a low-end Category 1 hurricane on the Saffir–Simpson scale—on 26 March. At that time, it was unofficially named Catarina and was also the first hurricane-strength tropical cyclone ever recorded in the Southern Atlantic Ocean. Abnormally favorable conditions persisted, resulting in Catarina intensifying further, and it would peak with 1-minute sustained winds of on 28 March. The center of the storm made landfall between the cities of Passo de Torres and Balneário Gaivota, Santa Catarina soon after. Catarina rapidly weakened upon landfall and dissipated later that day.

Catarina was the first tropical cyclone to make landfall in Brazil since the beginning of reliable records; hence, the infrastructure and population were not specifically prepared for it, which led to severe damage. Although the storm was an unprecedented event, Brazilian officials took the appropriate actions and warned the public about the approaching storm. Residents heeded the warnings and prepared for the storm by either evacuating or by riding it out in their homes. Catarina ended up destroying 1,500 homes and damaging around 40,000 others. Agricultural products were severely damaged: 85% of the banana crops and 40% of the rice crops were lost in the storm. Three fatalities were caused by the storm and 185 more were injured. Catarina would cause around $350 million (2004 USD) in damages.

Meteorological history

On 12 March, a cold-core stationary upper-level trough became established offshore of southern Brazil. A disturbance formed within the trough on the 19 March, and moved east-southeastward until 22 March, when a ridge to its southeast kept it stationary. With exceptionally favorable upper-level winds and slightly below average wind shear, as well as marginally warm water temperatures from , it gradually developed tropical characteristics, resembling a subtropical storm by the 24 March. Located east-southeast of Florianópolis, it headed slowly westward, and appeared to become a tropical storm on 25 March.

A compact storm, the cyclone continued westward while steadily intensifying. The structure of the storm continued to improve, and due to a definite eye feature showing on satellites, the storm was determined to have become a hurricane-equivalent cyclone on 26 March. The storm attained wind speeds of —equivalent to a low-end Category 1 hurricane on the Saffir–Simpson Hurricane wind scale (SSHWS)—on 26 March, making the cyclone the first hurricane-strength tropical cyclone ever recorded in the Southern Atlantic Ocean. Around this time, a Brazilian newspaper had a headline "Furacão Catarina" (i.e. "hurricane [threatening the state of Santa] Catarina"). Partially because of this headline, the storm was unofficially named Catarina. Unusually favorable conditions persisted and Catarina continued to intensify, and Catarina was estimated to have peaked with 1-minute sustained winds of on 28 March. Catarina continued to encounter favorable conditions and reached its peak intensity on early 28 March, with a minimum central pressure of and estimated 1-minute sustained winds of , which made the storm the equivalent of a Category 2 hurricane on the Saffir–Simpson scale. Wind gusts peaked at around . Soon afterward, the hurricane made landfall on the southern coast of Santa Catarina and northeastern Rio Grande do Sul, with winds up to overnight. After making landfall, Catarina rapidly weakened over land, in the normal manner of a tropical cyclone, dissipating later that day.

North American forecasters considered this storm a hurricane immediately upon reviewing the satellite-derived evidence. Since Catarina had a clear eyewall structure bounded by deep convective, dense central overcast, well-defined spiral outer bands and outflow structure, warm water temperatures of , little shear, a warm core low, overall tropical characteristics, and occurred in March (equivalent to September in the Northern Hemisphere, the peak of hurricane season), it was considered to be a hurricane by the National Hurricane Center (NHC) in the United States.

Though it is most commonly known as Catarina, all names for this storm are unofficial, as it was not named by any hurricane-monitoring meteorological agency affiliated with the World Meteorological Organization (WMO). (Tropical cyclone names are predetermined by an international committee of the WMO.) It has also been unofficially called "Aldonça", and the advisory names for it were "01T-ALPHA" from the United Kingdom's Met Office, and "50L-NONAME" from the United States' National Hurricane Center, which keeps it well outside normal designation, which start at 01L for designated storms and use 90L to 99L for invests. While Catarina formed in an unusual area, its relation to global warming or any other type of global climatic change is still up for debate. The attributed it to "climatic changes and atmospheric anomalies", However, more research in the area is still needed to make a conclusion.

At Passo de Torres, many shipyards were destroyed, as they were not designed to withstand the pressure differentials caused by Catarina's winds; widespread roof damage was reported at this municipality as well. Near the Mampituba River, a house was blown about upstream, literally landing in another state: it originally was built in the Torres municipality of Rio Grande do Sul, yet it ended up in Passo de Torres, within Santa Catarina. In rural areas, the corn, banana, and rice fields received the most damage, although rice farmers were able to partially recoup their losses, as they had harvested before Catarina made landfall.

A 2021 study found that the hurricane adversely affected children in utero, leading to reduced birth weight and increases in fetal deaths, possibly due to maternal stress.

See also

  • Subtropical Storm Arani (2011) – The first system officially named by the Brazilian Navy
  • Mediterranean tropical-like cyclones
  • Unusual areas of tropical cyclone formation
  • 2006 Central Pacific cyclone
  • 2005 storm in Uruguay
  • 1996 Lake Huron cyclone
  • Subtropical Cyclone Katie
  • Subtropical Cyclone Lexi
  • Cyclone Yaku

References

Further reading

; Informal studies and summary pages

  • Penn State write-up
  • Workshop on the Phenomenon Catarina (Brazilian Society of Meteorology)
  • Hurricane Catarina (Cooperative Institute for Meteorological Satellite Studies (CIMSS))
  • NOAA satellite and Dvorak info
  • Rare South Atlantic Tropical Cyclone (NASA)

; Media

  • "First South Atlantic hurricane hits Brazil" (USA Today)