Australia saw twelve tropical cyclones develop in its waters during the 2024/25 tropical cyclone season, the most in a season since 2005/06.

The 2024/25 tropical cyclone season, which runs from November to April, was overall a busy one but was a tale of two halves. The Western Region (extending from the NT-WA border to 90°E) had its most active season in 41 years, with eleven tropical cyclones.

Image: Summary of the 2024/25 tropical cyclone season

In contrast, the Northern Region (NT plus the Gulf of Carpentaria) did not record a single tropical cyclone, the first time that has occurred since the 2008/09 season. The Eastern Region (Tip of Cape York to 160°E) only recorded one; the infamous Tropical Cyclone Alfred.

Severe Tropical Cyclones

This season saw a high number of severe tropical cyclones, with eight cyclones reaching at least category 3, the most since the 2005/06 season, although this season saw more systems reach categories 4 and 5. From mid-January to late February, there was a run where all six of the tropical cyclones that formed during that period became severe. The high number of severe tropical cyclones is likely correlated with the record-high ocean temperatures during the season.

Image: The eight severe tropical cyclones that developed during the 2024/25 season. Source: NASA Worldview

Severe Tropical Cyclone Zelia was the strongest tropical cyclone of the season, reaching category 5, packing sustained winds of 205km/h, and a central pressure of 927hPa. Severe Tropical Cyclone Courtney also made it to category 5, with similar wind strengths, but a slightly higher pressure of 933hPa. 

Low number of coastal crossings

Despite the huge number of cyclones this season, only two tropical cyclones made landfall over the Australian mainland at cyclone strength: Zelia and Dianne. Alfred and Errol weakened below tropical cyclone strength just before landfall but may be reevaluated post-season. These four systems produced estimated insured losses exceeding $1.55 billion AUD, primarily from Zelia and Alfred, making it the most expensive season since the 2017/18 season with Tropical Cyclone Debbie.

Two tropical cyclones, designated Tropical Lows 09U and 25U, were declared to have reached tropical cyclone status during post-event analysis by the BoM. Since the BoM are the designated authority for tropical cyclones in the Australian region, each system is reevaluated afterwards to finalise tracks and strengths. There is also a review whether to permanently retire some names from the list of tropical cyclone names. Another area of interest will be evaluating the peak strength of Severe Tropical Cyclone Errol, as some sources suggest it briefly reached category 5.

Overall, the 2024/25 tropical cyclone season was simultaneously very busy and quiet for different parts of the Australian region but still featured several significant systems that will be remembered for a while to come.