The 2025–26 Australian region cyclone season was an annual cycle of tropical cyclone formation in the Southern hemisphere, marked by an unusually rapid succession of storms during the early months. It was the fourth consecutive season to have 5 or more severe tropical cyclones, a streak that began in 2022-23. The season officially ran from 1 November 2025 to 30 April 2026, activity began as early as mid-July with the formation of a tropical low. The season was defined by an exceptionally strong start, with six named systems developing by early January—the most active opening to a season in the region since 1983–84.
The heightened activity was largely driven by record-breaking sea surface temperatures and a significant negative Indian Ocean Dipole (IOD) event, which reached its lowest weekly value on record in November. These conditions provided ample fuel for intensification, resulting in a high proportion of severe tropical cyclones. The strongest system of the year was Severe Tropical Cyclone Maila, which reached Category 5 intensity in April and became the most powerful storm recorded in the Port Moresby area of responsibility.
Season summary
The accumulated cyclone energy (ACE) for the 2025–26 Australian region cyclone season is 99.5 units. The Indian Ocean Dipole reached -1.94°C in the week ending 2 November, which was the lowest weekly ever recorded in records to 2008. A negative IOD influences tropical cyclone development in the Indian Ocean, as it leads to warmer water near Australia. Twenty-three tropical cyclones formed, eleven of which were named storms, and seven of them became severe tropical cyclones.
The season began with a tropical low in TCWC Jakarta's area of responsibility on 15 July. It was the first July tropical low in the Australian region since 2022. It moved into the South-West Indian Ocean a day later. The first tropical cyclone of the season, Fina, formed in the Timor Sea on 18 November. Fina quickly intensified to a Category 4 on the Australian Scale peak before landfall on the western part of the Northern Territory. This was followed by Bakung, which also became a Category 4 Severe Tropical Cyclone on 14 December before dissipating, looping around in the northwestern part of the basin, away from land. After that, Grant developed, and slowly intensified before leaving the basin on 27 December. The same day, Hayley developed. It struck Kimberley a few days later, weakening from its Category 4 peak.
To continue the quick formation of storms, Iggy was a short-lived Category 1 system well away from land in early January, before Jenna also curved westward a few days later, as a Category 3. The Australian region has seen an unusually active start to the season, with six named systems forming or entering Australia's western region by 6 January, making it the most active in the region to said point since the 1973-74 season. Continuing with a very active streak, Koji was a weaker system that impacted Queensland in mid–January. After a short break, Luana formed and struck near Broome on 25 January, before continuing inland via a brown ocean effect. In early February, Mitchell developed and paralleled the Pilbara coast before making landfall on 9 February. After that, a much longer break between named storms occurred. Cyclone Narelle developed in the northern Coral Sea on 15 March. Maila formed in the Solomon Sea on 4 April, and was the first named cyclone in the Port Moresby area of responsibility since Guba in the 2007, which days later became the second Category 5 tropical cyclone and the strongest of the season.
Systems Tropical Low 01U
On 15 July, a low-pressure area that had developed out of an equatorial trough which interacted with the Madden-Julian Oscillation gained better characteristics, thus it was noted as the first tropical low, in the area of responsibility of TCWC Jakarta. It was the first July tropical low in the Australian region since 2022. As the system slowly intensified in an area of warm SSTs offset by high wind shear, a TCFA was issued by the JTWC, shortly before the system exited into the South-West Indian Ocean basin on 16 July, where it was designated Tropical Depression 01 by MFR.
Severe Tropical Cyclone Fina
On 15 November, the Bureau of Meteorology started tracking a low-pressure system near the Timor Sea and designated it as 02U. On 18 November, the system developed stronger convection and thunderstorm activity. It intensified into Tropical Cyclone Fina on the same day and remained a compact system. On 19 November, Fina intensified into a Category 2 cyclone amid warm sea surface temperatures. A cyclone warning was issued from the Coburg Peninsula to Warruwi, and a cyclone watch was issued for the Tiwi Islands, Maningrida, and Milingimbi Island. Curved banding was visible early on 20 November as Fina began moving south towards the Top End. Fina weakened later that day as it continued moving south due to wind shear, and its convection decreased. It slightly re-intensified that evening as it moved towards Darwin. Fina made landfall on the Coburg Peninsula on 21 November and further intensified as it moved into the Van Diemen Gulf. Early on 22 November, Fina strengthened into a Category 3 severe tropical cyclone. Fina made its second landfall on Melville Island that morning, with an eye being visible on satellite imagery. The cyclone slightly weakened but maintained category 3 intensity that afternoon as it emerged into the Timor Sea, and its eye became less defined following the interaction with land. On 23 November, Fina strengthened into a category 4 cyclone, with a clearly visible eyewall persisting on radar imagery and a minimum central pressure of . On 24 November, Fina then weakened to category 3 intensity and made landfall near the mouth of the Berkeley River along the northeastern coast of Kimberley. Once inland, Fina rapidly weakened to a tropical low and dissipated on 26 November.
On 19 November, a cyclone warning was issued from the Cobourg Peninsula to Warruwi, and a cyclone watch was issued for the Tiwi Islands, Maningrida, and Milingimbi Island. On 1:09 am ACST on Friday 21 November 2025, the Northern Territory Emergency Service issued cyclone warnings for part of the Northern Territory. The Darwin Airport closed at 9 AM ACST in preparation for the cyclone, and shelves were empty in some stores across Darwin as major supermarkets were advised to close across the region. The local hospital, Royal Darwin Hospital, issued a code brown to streamline emergency management systems. The strongest wind gusts were recorded were around 109 km/h at Crocker Island Airport on 21 November, and 107 km/h in 22 November. The most notable 24-hour rainfall recorded from Fina was at Middle Point, near Darwin, which would record 430 millilitres in the 24 hours to the morning of 23 November. Across 22 and 23 November, the system caused several significant power outages, including large parts of Darwin, Palmerston, and the Tiwi Islands, affecting at least 19,500 customers. Roads were flooded, and properties were damaged. Hundreds of trees fell across Darwin, damaging cars and homes, while parts of the Royal Darwin Hospital's external wall collapsed. Losses totaled to AU$84 million (US$60.3 million).
Severe Tropical Cyclone Bakung
On 10 December, a low pressure area formed to the south of the city of Jakarta. Although the system was outside its area of responsibility at the time, the Bureau of Meteorology designated it Tropical Low 05U. 05U then began moving southwest, and began to consolidate and wrap deep convection near its centre, and was named Bakung by TCWC Jakarta on 12 December. The cyclone developed rapidly in an environment of low wind shear, reaching its peak intensity as a category 4 on 14 December, and had moved into the Australian area of responsibility. High wind shear led to a weakening of the system during 15–16 December, before easing and allowing Bakung to intensify to a category 3 early 17 December. The wind shear then rapidly increased, weakening the system to a tropical low before dissipating on 18 December.
Tropical Cyclone Grant
On 16 December, a tropical disturbance, designated as Tropical Low 03U by the Bureau of Meteorology (BoM), formed south of Indonesia and began to move west. On 18 December, the Joint Typhoon Warning Center (JTWC) initiated advisories on the system, designating it as Tropical Cyclone 09S, noting that westerly wind shear was causing convection within the system to displace to the west. On 22 December, the JTWC advised that the system began to slow its forward motion speed due to a switch in a steering flow among a split subtropical ridge. The following day, the BoM upgraded the system to a category 1 tropical cyclone on the Australian scale and was assigned the name Grant, with the JTWC noting that convection within the system was improving due to a decrease in wind shear. However, later that day, the JTWC noted an increase in northerly wind shear and a decrease in convection and the BoM downgraded Grant to a tropical low early the next day. The following day, the BoM re-upgraded Grant to a category 1 tropical cyclone, with the JTWC noting an increase in convective banding and the cooling of the cloud tops within the system. Grant continued to strengthen, with the BoM upgrading the cyclone to category 2 intensity the next day before entering La Reunion's area of responsibility on 27 December.
Grant brought heavy rainfall and gale-force winds while passing close to the Cocos (Keeling) Islands. However, minimal damage was reported.
Severe Tropical Cyclone Hayley On 27 December, a tropical low, designated as Tropical Low 08U by the Bureau of Meteorology (BoM), formed north-northeast of Broome. The low began moving south and intensify. The following day, the Joint Typhoon Warning Center (JTWC) initiated advisories on the system and designated it as Tropical Cyclone 10S. The JTWC observed that convective banding was wrapping around the centre. Later that same day, the BoM to upgraded it to a category 1 tropical cyclone on the Australian scale and assigned it the name Hayley. Shortly after, it began a period of rapid intensification, with the JTWC observing convection developing in the southwestern quadrant of the storm, along with an eye-like feature beginning to appear on satellite imagery. The BoM then upgraded Hayley to category 4 strength late on 29 December. Early the next day, Hayley weakened slightly to category 3 strength and turned east-southeast toward the Dampier Peninsula. The following day, Hayley made landfall near the communities of Lombadina and Djarindjin. After crossing King Sound, Hayley moved inland over Western Australia once again and began to weaken, with the JTWC observing that land interaction was beginning to impinge on the centre of circulation within the cyclone. Hayley then weakened below tropical cyclone strength late on 30 December and dissipated early the next day.
Portions of Western Australia received at least of rain fell in a 48 hour period, the equivalent to two to three months worth of rainfall for the region. The deluge led several rivers overflowing their banks. Flooding damaged several highways, isolating remote communities. Wind gusts up to were reported in the Lombadina community. North of Broome, strong winds tore off the roofs of two homes. A basketball court sustained severe damage from the storm. Water leaked through the roofs of several homes. A tree fell on a parked car in One Arm Point. Another fallen tree damaged the roof of a church in Djarindjin. Several communities were left without power and nine people fled to shelters. A bridge was temporarily closed after a tree fell on it. After the storm, seventeen State Emergency Service volunteers were mobilized to assist with recovery efforts. Losses totaled to AU$2.4 million (US$1.72 million).
Tropical Cyclone Iggy