Deadly Tropical Cyclone Freddy is set to break records for the longest-lasting storm of its kind as it appears on course to hit Mozambique for a second time, more than two weeks after the first.

The cyclone has already caused immense damage in Mozambique and Madagascar, killing at least 21 people across both countries and displacing many thousands of others.

It is a “very rare” storm, according to the World Meteorological Organization (WMO), which has called Cyclone Freddy’s journey so far “incredible and dangerous.”

It developed on February 6 off the northwest Australian coast, before tracking thousands of miles across the South Indian Ocean towards southeast Africa, affecting the islands of Mauritius and La Réunion on the way.

The storm hit the eastern coast of Madagascar on February 21 before slamming into Mozambique a few days later, bringing torrential rain, destructive winds and flooding which has destroyed houses and affected nearly 2 million people.

“Freddy is having a major socio-economic and humanitarian impact on affected communities,” Johan Stander, WMO services director, said in a statement.

It then looped back out towards the Mozambique Channel, gaining energy from the warm waters, and headed towards the southwestern coast of Madagascar.

The cyclone is now moving away from the area and expected to intensify as it heads back towards Mozambique, where it could make landfall for a second time later this week, according to the WMO.

Freddy, which meteorologists say has intensified six times, has already broken Southern Hemisphere records for the highest “accumulated cyclone energy,” referring to its strength over time.

The WMO is monitoring whether Freddy will become the longest-lasting cyclone in the world, beating the current record which is held by Typhoon John, which lasted for 31 days in 1994.

“At this time, it does appear to be a new record holder for ‘longest-lasting’ recorded tropical cyclone … but we are continuing to monitor the situation,” WMO Weather and Climate Extremes Rapporteur Randall Cerveny said in a statement on Tuesday.

While it is too early to say what impact the climate crisis has had on Cyclone Freddy, scientists have said that climate change is making these tropical storms more intense and powerful.