Australia's 2024–25 northern wet season
Issued
Summary
- Averaged across Australia north of 26°S, the wet season (October 2024 to April 2025) rainfall was 566.9 mm, which was 21% above the 1961–1990 average of 476.4 mm.
- Rainfall was above average for most of Queensland, much of northern Western Australia and in scattered areas of the Northern Territory.
- Rainfall was average to below average for most of the Northern Territory, with the monsoon onset date at Darwin of 7 February 2025 being the latest since records began there in 1957–58.
- The northern rainfall onset date (the date when rainfall accumulated since 1 September reached 50 mm) was up to 6 weeks earlier than average in Western Australia and the Northern Territory, but later than average for central and eastern Queensland.
- The mean maximum temperature across northern Australia for the wet season was 1.61 °C above the 1961–1990 average, the fifth-warmest on record, since national observations started in 1910, and the mean minimum temperature was 1.67 °C above average, the warmest on record.
- Sea surface temperatures (SSTs) around northern Australia were the warmest on record since 1900–01, at 0.67 °C above the 1991–2020 average. SSTs in the Coral Sea were also warmest on record, while SSTs off the north-west coast of Western Australia reached 3 °C above average at times.
- Wet conditions in northern Australia, particularly in November and December 2024, resulted in increased inflow to water storages. Major storages including Lake Argyle, Tinaroo Falls, Fred Haigh, Burdekin Falls, and Teemburra Dam, finished the season at their full supply capacity.
- There were 12 tropical cyclones in the Australian region from October 2024 to April 2025, the most since 2005–06 and slightly above the average of 11 for all years since 1969–70, or the average of 9 since 2000–01.
- Two tropical cyclones (Zelia and Dianne) made landfall on the Australian mainland at tropical cyclone strength, below the long-term average. Alfred and Errol made landfall at tropical low strength, with significant impacts from both systems.
Rainfall
Rainfall totals
The total area-average rainfall for northern Australia over the 2024–25 wet season (October 2024 to April 2025) was 566.9 mm, which was 21% above the 1961–1990 average of 476.4 mm. Rainfall was above average for most of Queensland, much of the north of Western Australia, and scattered areas in northern, eastern and southern Northern Territory.
Rainfall was very much above average (in the highest 10% of all wet seasons since 1900–01) for large areas of Queensland and parts of the Kimberley and Pilbara districts in Western Australia. This included small pockets of highest on record wet season rainfall, most notably along the Queensland coast between Townsville and Ingham.
Rainfall was average to below average for most of the Northern Territory.
Rainfall timing
Much of the west of northern Australia saw an earlier than average (relative to the 1981–2010 period) northern rainfall onset date (the date when rainfall accumulated since 1 September reached 50 mm). Large areas had an onset date at least 6 weeks earlier than average, notably in the inland Pilbara in Western Australia and areas of the Tanami and Lasseter regions in the Northern Territory.
In contrast, parts of the Top End and east of the Northern Territory, and most of eastern and south-western Queensland, experienced a later-than-average northern rainfall onset date.
After near-average rainfall in October, the November and December rainfall was 76% and 49% above average respectively. In contrast, January rainfall was 29% below average, the lowest since 1994. January rainfall was below average to very much below average for most of the Northern Territory and inland Queensland and small areas of the north of Western Australia. This was caused by a delayed start to the monsoon across most of northern Australia. The monsoon onset date at Darwin was 7 February 2025, the latest since records began in 1957–58, surpassing the previous latest onset date of 25 January (during the 1972–73 wet season).
Rainfall for February, March and April for northern Australia overall was 12%, 47% and 57% above average respectively. In February, the Pilbara region in Western Australia experienced very much above average rainfall, and highest on record along the coast, from Severe Tropical Cyclone Zelia. Parts of the north tropical coast of Queensland received record rain in February from Tropical Low 13U and an associated monsoonal trough.
In late March, south-western Queensland experienced extreme rainfall from the passage of a slow-moving inland trough. Many areas received more than 4 times their March average. Between 23 and 26 March, some locations recorded more than their annual average rainfall.
Temperature
Maximum temperature
The mean maximum temperature across northern Australia for the 2024–25 wet season was 1.61 °C above the 1961–1990 average, the fifth-warmest on record, since national observations started in 1910, and the mean minimum temperature was 1.67 °C above average, the warmest on record.
Mean maximum temperatures were above to very much above average (in the warmest 10% of all wet seasons since 1910–11) across most of northern Australia. Parts of south-eastern Northern Territory and Queensland's far south-west experienced their highest mean maximum temperatures on record for the wet season period.
Northern Australia's area-averaged maximum temperature was warmer than average for each month of the wet season, at more than 1 °C above average, except for April. For October 2024 and January 2025, area-averaged maximum temperatures were the second-warmest on record for their respective months, at 2.57 °C and 2.58 °C above average.
Minimum temperature
Mean minimum temperatures were above to very much above average across northern Australia. Mean minimum temperatures were warmest on record for parts of the Kimberley and Pilbara districts in Western Australia, parts of the Simpson and Lasseter districts in the Northern Territory, the north of Cape York Peninsula, and parts of the Gulf Country and Channel Country in Queensland.
Northern Australia's area-average minimum temperature was warmer than average for each month of the wet season. For all months except April, they were in the top 5 warmest on record for their respective month. The March area-average minimum temperature was the warmest on record for the month, 2.31 °C above average. Large parts of southern and western Northern Territory, extending into western Queensland, and areas in Western Australia had their highest March minimum temperatures on record.
Water availability
At the start of the 2024–25 northern wet season, soil moisture in the root zone (in the top 100 cm) was very much above average (in the highest 10% of all years since 1911) in most northern parts of Western Australia and Northern Territory. In October, above average rainfall in Western Australia and the Top End maintained soil moisture above to very much above average. In contrast, much of Queensland experienced below average soil moisture due to low rainfall. Most streamflow sites were at their historical averages, except for some in the Top End and northern coastal Queensland, which observed the highest flows on record due to localised heavy rainfall. Major storages, including Lake Argyle, Tinaroo Falls and Fred Haigh remained above 90% full at the end of October.
Rainfall in November was very much above average across much of northern Australia, helping to improve soil moisture in large parts of northern Quensland. In December, heavy rainfall continued in much of Western Australia and along the north-east and south-east Queensland coast. This led to increased soil moisture across most areas of northern Australia and subsequent high streamflow. Very much above average streamflow was observed in many sites, resulting in riverine and flash flooding in these areas. High streamflow also helped to increase water levels in the storages, with a number of large storages, including the Lake Argyle, Burdekin Falls, Teemburra Dam and Tinaroo Falls reaching 100% capacity.
Northern Australia received its lowest January rainfall since 1994, decreasing soil moisture to below average across a large area of central northern Australia. The dry conditions impacted streamflow at some sites in the Carpentaria Coast and Tanami-Timor Sea Coast drainage divisions, which recorded their lowest January flows on record since 1975. However, Severe Tropical Cyclone Sean brought heavy rainfall to parts of Western Australia's Kimberley, Pilbara and Gascoyne districts, helping to maintain above average soil moisture and increasing storage levels in the Harding Dam.
In February the monsoon's arrival brought heavy rainfall to the tropical north. The monsoon trough moved inland over northern Queensland and brought heavy rainfall to the Gulf of Carpentaria and the north-east tropical coast, and led to major flood warnings for the Haughton, Herbert and Upper Burdekin rivers. As a result, increased soil moisture and high streamflow were observed in the area. In mid-February, ex-Tropical Cyclone Zelia also brought heavy rainfall across the Pilbara in Western Australia, causing major flooding of the De Gray River.
In March average to below average rainfall across the northern and western parts of the Northern Territory and much of Western Australia led to declines in soil moisture and low streamflow in the area. In contrast, Queensland saw its second-wettest March on record (highest since 2011), resulting in major flooding across widespread areas of inland Queensland, and along the north-east and south-east coasts. This significantly increased soil moisture in the area, particularly across the Lake Eyre Basin. Some streamflow sites on Queensland's tropical east coast recorded their highest flows on record.
In April 2025 above to very much above average rainfall across eastern and northern parts of northern Australia led to increased soil moisture in the area. The majority of water storages were full, and most rivers were flowing above their historical average. In contrast, average to below average rainfall in western parts of Western Australia led to further declines in soil moisture and low streamflow. However, Severe Tropical Cyclone Errol resulted in the highest April rainfall on record at some sites in northern Western Australia, increasing soil moisture in the area.
Atmosphere and oceans
The record or near-record warmth in global sea surface temperatures (SSTs) since April 2023 was reflected in the waters around northern Australia in the 2024–25 northern wet season. For the northern tropical region overall (defined as waters between 4°S and 22°S, and 94°E and 174°E), the 2024–25 northern wet season SSTs were the warmest on record since 1900–01, at 0.67 °C above the 1991–2020 average, and 0.24 °C above the previous record set in 2015–16. October, November, December and January were all warmest on record for their respective months, with March and April second-warmest, and February fourth-warmest.
Coral Sea SSTs were warmest on record for the 2024–25 wet season. SSTs in the north-west region were 2nd warmest on record with anomalies close to Western Australia's coast exceeding 3 °C above average at times during the season.
In the central tropical Pacific, SSTs cooled throughout 2024, approaching La Niña-like temperatures towards the end of the year and into early 2025. Values of the Niño3.4 SST index were lowest in January, before warming to a neutral state in the latter part of the season. The Southern Oscillation Index (SOI), an atmospheric component of the El Niño–Southern Oscillation (ENSO), showed no coherent signal through the northern wet season. This suggests that the La Niña-like conditions had limited influence on the Australian northern wet season. However, trade winds and cloudiness near the Date Line were consistent with La Niña-like conditions for several months.
The Indian Ocean Dipole (IOD) remained neutral for the 2024–25 northern wet season. In September, cooler than average temperatures emerged off the Horn of Africa, and warm anomalies off the Indonesian islands of Java and Sumatra. These strengthened in October, resulting in the weekly IOD index dropping below the negative IOD threshold (−0.4 °C). The IOD index remained below this threshold for 7 consecutive weeks during October and early November, although this was not long enough to be considered a negative IOD event. IOD index values returned to neutral in early December as SST anomalies in both the western and eastern Indian Ocean weakened.
The Madden–Julian Oscillation (MJO), modulates rainfall patterns and tropical cyclone potential in the region on weekly to monthly timescales during the northern wet season. From late November to mid-December, there was a particularly active pulse of the MJO over the Australian longitudes, which likely contributed to increased tropical activity and above average rainfall over large parts of northern Australia, However, this activity was not sufficient to trigger the onset of the Australian monsoon.
MJO activity did not return to the Australian region until late January to early February, with a moderate strength pulse. The lack of MJO activity likely contributed to the unusually late onset of the monsoon over northern Australia. At Darwin, the official monsoon onset date was 7 February 2025, the latest onset since records began in 1957–58. While the monsoon didn't arrive in Darwin until early February, the monsoon trough was established over northern Queensland towards the end of January and also briefly in northern Western Australia.
There was another weak pulse of the MJO in the Australia region in mid-March, likely contributing to heavy rainfall at this time.
Tropical cyclones
- For the Australian region, defined for tropical cyclones as between 90°E and 160°E south of the equator, there were 12 tropical cyclones that formed during the northern wet season, the most since 2005–06.
- The long-term average (since 1969–70) number of tropical cyclones in the Australian region is 11, while in recent decades (since 2000–01) the average is 9.
- Eight tropical cyclones reached severe strength (at least category 3) while in the Australian region, the most since 2005–06. Two tropical cyclones, Zelia and Courtney, reached category 5.
- There were 11 tropical cyclones in the western tropical cyclone region, between 90°E and 125°E, the most since 1999–2000.
- Two tropical cyclones (Zelia and Dianne) made landfall on the Australian mainland at tropical cyclone strength, below the long-term average. In addition, Alfred and Errol both crossed at tropical low strength, while Sean impacted some coastal areas while remaining offshore.
- There were 6 simultaneous potential tropical lows (12U to 17U) monitored in early February, which has not occurred in Australia's Area of Responsibility, in the last 20 years.
Tropical Cyclone Robyn
- Tropical low 01U formed in the Indian Ocean, south-west of Sumatra, on 23 November with an active pulse of the Madden-Julien Oscillation (MJO) and Kelvin wave activity.
- The low developed into Tropical Cyclone Robyn on 28 November to the south-west of Cocos (Keeling) Islands and tracked south-eastwards with no impact on the islands.
- Robyn was a short-lived cyclone that peaked at category 2 intensity late on 28 November, before rapidly weakening on 29 November.
- Robyn was the first tropical cyclone in the Australian region for the 2024–25 season.
- Tropical Cyclone Robyn did not impact the Australian mainland or island communities.
Tropical Cyclone 09U Unnamed
- Tropical low 09U formed south of Christmas Island on 8 January and moved on a general south-westerly track over open waters of the Indian Ocean until weakening on 13 January.
- Following post-event analysis, it was found that 09U briefly reached category 1 strength on 10 January, and the system has retrospectively been given tropical cyclone status.
- Unnamed Tropical Cyclone 09U did not impact the Australian mainland or island communities.
Severe Tropical Cyclone Sean
- Tropical low 11U formed just off the west Kimberley coast on 17 January and tracked to the west south-west off the Pilbara coast, reaching tropical cyclone strength on 19 January.
- The low developed into tropical cyclone Sean early on 19 January and quickly intensified to peak at category 4 intensity on 20 January.
- Severe tropical cyclone Sean weakened well off the west coast on 22 and 23 January.
- Gales were reported along parts of the Pilbara coast between Roebourne and Exmouth on 19 and 20 January.
- Karratha Aero exceeded its highest daily rainfall record and January monthly total records when 274.4 mm fell in the 24 hours to 9 am on 20 January. There were reports of water ingress, flooding, and property damage due to fallen trees.
- Sean was the first cyclone to reach severe intensity in the 2024–25 season in the Australian region.
Severe Tropical Cyclone Taliah
- Tropical low 14U formed offshore north-west of the Kimberley coast on 31 January and reached tropical cyclone intensity well north of the Pilbara coast on 2 February.
- Taliah maintained a westward track as it reached its highest intensity of category 3 between 3 and 4 February, before weakening to below tropical cyclone intensity between 5 and 7 February.
- Taliah regained tropical cyclone intensity as the system turned south-west and reached category 2 between 10 and 11 February before leaving the Australian Area of Responsibility on 12 February.
- Taliah was a long-lived system, lasting 13 days within Australia's Area of Responsibility, although it was briefly below tropical cyclone strength for a few of days.
- Severe Tropical Cyclone Taliah did not impact the Australian mainland or island communities.
Severe Tropical Cyclone Vince
- Tropical low 15U formed south of Christmas Island on 31 January and reached tropical cyclone intensity on 2 February.
- Vince reached category 3 while tracking westward before moving past the western boundary of the Australian region (90°E) on 4 February.
- Severe Tropical Cyclone Vince did not impact the Australian mainland or island communities.
Severe Tropical Cyclone Zelia
- Tropical low 18U formed off the north-west Kimberley coast on 8 February and tracked offshore for several days.
- The low developed into Tropical Cyclone Zelia on 12 February when the system was to the west of Broome.
- Zelia was a small but very intense cyclone, becoming near stationary and rapidly strengthening to category 5 intensity on 13 February.
- The system turned and began to move south-easterly towards the Pilbara coast early on 14 February and weakened to a category 4 before it made landfall at 12:30 pm AWST near the De Grey River mouth, to the east of Port Hedland.
- Zelia was downgraded to a tropical low during the evening of 14 February near Marble Bar.
- Zelia was associated with damaging winds, widespread heavy rainfall and flooding impacts in the Pilbara region and south-western parts of the Kimberley district.
- While the very destructive core missed Port Hedland, the town experienced 7 hours of damaging winds with a maximum gust of 120 km/h, while Marble Bar reported gusts up to 109 km/h as the weakening system passed.
- The De Grey and Pardoo stations on the Pilbara coast exceeded their annual highest 3-day rainfall totals at 580.4 mm and 518.2 mm, respectively, to 9 am on 14 February. Both stations also recorded their highest daily February rainfall on record during this event with 261.0 mm to 9 am 14 February and 228.0 mm to 9 am on 13 February, respectively. Surrounding areas received over 200 mm between 11 and 17 February.
- Flooding caused some remote communities to be evacuated and temporarily closed many roads including a section of the Great Northern Highway, isolating Pilbara and Kimberley communities from southern Western Australia.
- Shipping and offshore oil and gas operations were disrupted through activity ceasing and port closures that resulted in significant economic costs to industry.
- Zelia was the first tropical cyclone to make landfall on the Australian mainland in the 2024–25 season, the latest first crossing since the 2016–17 season.
Severe Tropical Cyclone Alfred
- Tropical low 22U formed north-east of Cooktown on 21 February and tracked eastward for several days and was named Tropical Cyclone Alfred on 23 February.
- Alfred turned southward and continue to strengthen to a peak intensity of category 4 on 27 February.
- Alfred began to weaken reaching category 1 intensity well offshore to the east of Rockhampton by 2 March.
- Alfred was steered to the south-east while fluctuating between category 1 and category 2 intensity between 2 and 4 March, before the system turned abruptly to track westwards towards south-east Queensland.
- Alfred had a slow and sometimes erratic motion as it moved westward, weakening to a category 1 intensity before the system made landfall at Moreton Island around 1:00 am AEST 8 March and weakened below tropical cyclone strength around 6:00 am AEST 8 March to the east of Bribie Island.
- Ex-Tropical Cyclone Alfred crossed Bribie Island around 8:00 pm AEST 8 March, and then the mainland at 9:00 pm AEST 8 March.
- Alfred was associated with damaging wind gusts, heavy rainfall with subsequent flooding and severe coastal erosion of beaches in south-east Queensland and northeastern New South Wales.
- Alfred led to rainfall totals greater than 100 mm recorded across large regions between Queensland's south-east and north-eastern New South Wales, with totals greater than 400 mm in parts of the Northern Rivers and Mid North coast districts of New South Wales and Queensland's South East Coast, and Wide Bay and Burnett districts.
- Severe Tropical Cyclone Alfred was a long-lived system and the only cyclone to occur in the eastern tropical cyclone region in the 2024–25 season.
Severe Tropical Cyclone Bianca
- Tropical low 21U formed to the north-west of the Kimberley on 18 February, then tracked south-west well offshore of the Kimberley and Pilbara coast for several days.
- The system developed into Tropical Cyclone Bianca at 8:00 pm AWST 23 February, peaking at category 4 intensity on 25 February.
- Bianca was steered southward and weakened below tropical cyclone strength on 27 February.
- Severe Tropical Cyclone Bianca did not impact the Australian mainland or Island communities.
Tropical Cyclone 25U Unnamed
- Following post-event analysis, it was found that tropical low 25U briefly reached category 1 strength on 19 March south of Cocos (Keeling) Island, and the system has retrospectively been given tropical cyclone status.
- Strong winds were recorded on Cocos Island overnight from 18 to 19 March but there were no reported impacts.
Severe Tropical Cyclone Courtney
- Tropical low 27U formed south of Bali on 21 March and tracked south-westward well offshore of the Australian mainland.
- The low developed into Tropical Cyclone Courtney on 26 March and was steered westward peaking at category 5 intensity just before crossing the western boundary of the Australian region (90°E) on 29 March.
- Severe Tropical Cyclone Courtney did not impact the Australian mainland or Island communities.
Tropical Cyclone Dianne
- Tropical low 28U formed in the Indian Ocean to the north-west of the Kimberley on 27 March.
- The low initially tracked eastward towards the Kimberley coast and then shifted southwards before strengthening to tropical cyclone intensity on 28 March.
- Dianne strengthened to a category 2 system as it made landfall close to Koolan Island at 2:30 am AWST on 29 March, where near storm-force winds were recorded.
- Dianne then weakened as it moved south over the Kimberley and Western Australia interior.
- Dianne was associated with heavy rainfall and flooding in western parts of the Kimberley.
- Weekly rainfall totals of 100 to 200 mm were recorded across the northern Kimberley, and 25 to 50 mm was recorded in the northern inland areas of Western Australia.
Severe Tropical Cyclone Errol
- Tropical low 29U formed to the north of the Northern Territory on 9 April and moved in a west to south-west direction through the Timor Sea.
- The low reached tropical cyclone intensity on 15 April north-west of the Kimberley.
- Errol slowed and peaked at category 4 intensity on 16 April before turning to the south-east and weakening below tropical cyclone strength on approach to the north-west Kimberley coast
- Ex-Tropical Cyclone Errol crossed near Kuri Bay on 18 April as a tropical low.
- Errol was associated with strong winds between Kuri Bay and Cockatoo Island and heavy rainfall between Mitchell Plateau and Cockatoo Island.
- Rainfall totals greater than 50 mm were recorded in parts of western Kimberley for the week ending 21 April.
Related information
- Area-average data and time series charts for the northern wet season period
- Rainfall maps for the 7-months periods ending April
- Wet season climate summary for Northern Territory
About the data
All values in this statement were compiled from data available as of 15 May 2025. Subsequent quality control and the availability of additional data may result in minor changes to final values.
The use of current and historical climate information allows for comparison of climate impacts from one year to the next and aligns with other reporting processes that occur over northern wet season periods.
This statement was prepared using the following sources:
- Rainfall maps from the Australian Gridded Climate Dataset (AGCD) analyses.
- Temperature maps from the Australia Water Availability Project (AWAP) analyses.
- Area-average time series for the northern wet season are calculated from the homogenised Australian temperature dataset (ACORN-SAT) and AGCD monthly rainfall.
- Root-zone soil moisture from Australian Water Resources Assessment Landscape model (AWRA-L) 7.0 analyses.
- Water storage information and the Murray-Darling Basin Information Portal.
- Sea surface temperature from the ERSSTv5 dataset.
- Tropical Cyclone information from tropical cyclone reports.
Unless otherwise noted, all maps, graphs and diagrams in this page are licensed under the Creative Commons Attribution 4.0 International Licence
