2017 South Atlantic Hurricane Season

The 2017 South Atlantic hurricane season had a extraordinarily rare major hurricane, which almost reached C4 status. The season ran from January to April.

Subtropical Storm Andre
In January 14, a cold front had developed and along with it a frontal system. Near the frontal system, a circulation developed on January 15. It had no baroclinity and moved away from the frontal system. On January 16, it had enough subtropical characteristics to be classified as a subtropical depression. Later on January 17, it entered a environment of 25ºC SST's and a rare occurence of no wind shear. It rapidly strengthened into, according to recon and ADT estimates, a 71 mph storm. It then rapidly dissipated into a trough in the afternoon of January 18. No damages were reported.

Tropical Storm Bill
In February 19, a disturbance was reported by several buoys/ships near the Amazon River. The disturbance rapidly traveled southeast and emerged into the South Atlantic Ocean, where it intensified into a tropical storm with 45 mph winds. It then approached a favorable environment and intensified into a 50, then 60, then 65 mph storm. It then went toward the huge pile of normal 90 kt wind shear and dissipated in 2 hours, on February 22. No fatalities were reported.

Major Hurricane Cão
Cão developed as a disturbance near Angola on February 24. It then encountered favorable and baroclinic-free conditions on February 25 in the middle of the ocean, which made it rapidly a weak tropical storm. Conditions unnormally became favorable in the area, which made the tropical storm intensify into a 75 mph hurricane. Later, it encountered more favorable conditions in a more baroclinic zone, but there was no baroclinic storms. Beacuse of that, it intensified into what is the equivalent of a Category 2 hurricane on the SSHS scale. Wind shear lowered and it became a Category 3 hurricane with 125 mph winds, almost a Category 4 hurricane. Then, it went into the 90 kt wind shear, which weakened it into a 25 mph depression, and it teared the storm apart very quickly. On February 28, it fully dissipated.