First of the season: Rare tropical storm in South Atlantic

An exceptionally rare storm is brewing in the Atlantic; both in location and time of year.

The first tropical storm of the year has already developed in the Atlantic. However the start of the hurricane season is still a long way off with an official start date of June 1st.

Of course tropical systems can still form outside of this date, however it is unusual. What is exceptional about this storm though is not even the time of year, but rather its location.

The tropical storm, already named Akará, is located off the coast of Brazil, south of Rio de Janeiro. According to our WindRadar, it is currently gusting at around 60 mph, but will likely not cause any danger to anyone.

Weather models indicate that the centre of Akará will move slowly to the south before dissipating. This means that the tropical storm will likely remain at a safe distance from the mainland, with no islands in this region either.

Akará is an exceptional storm, as they are extremely rare in the southern Atlantic. Most Atlantic cyclones form during the hurricane season from June to November north of the equator, and head towards the Caribbean and North America.

The reason for its rarity is for two reasons. Wind shear is often too strong in the South Atlantic basin to allow formation. Additionally, the birth of hurricanes originate from tropical waves off the coast of Africa, which don't happen south of the equator.

For this reason, there is no separate organisation responsible for monitoring and warning of tropical storms in the South Atlantic. The storms are named by the Brazilian Navy.

The last tropical storm there was in 2022; Hurricane Catarina in 2004, which reached a category 1 strength and left a path of devastation in Santa Catarina, Brazil.

It was also the only hurricane to ever be recorded in the South Atlantic; prior to the 21st century, no hurricane had ever been officially confirmed there before. Akará is also one of four known tropical storms here in the last 14 years.

In this instance, a low pressure system initially formed off the back of a cold front. A surge of tropical moisture from the north then got pulled down into the low.

A mix of instability and high water temperatures contributed to the formation of thunderstorms, which then moved closer to the low's centre, enabling a transition from nontropical to subtropical to tropical storm.