Australian Weather

Today, 1:47AM UTC

A cold front will bring a burst of cool, wet and windy weather to southwestern Australia later this week, putting Perth on track to have its coldest weekend in about eight months. May is typically the time of year when cold fronts start to become more active over southwestern Australia due to the seasonal northward shift of the subtropical ridge in the Southern Hemisphere. This increased frontal activity is why Perth’s average rainfall in May is close to double that of April, and mean maximum temperatures drop by about 4°C between the two months. This May’s first cold front will reach the southwest corner of WA late on Friday and reach Perth in the early hours of Saturday morning, before pushing further north and east into the weekend. The passage of the front will produce blustery winds, showers, thunderstorms and a noticeable drop in temperature across the southwest of WA on Friday into Saturday. Perth’s maximum temperature on Thursday is predicted to reach about 31°C in a warm air mass ahead of the approaching front. This will be Perth’s first May day over 30°C since 2018. By contrast, the city is only forecast to reach 21-22°C on Saturday and Sunday, which would make it Perth’s coldest weekend since September. Showers accompanying the frontal system should deliver about 5 to 25mm of rain over western and southwestern districts of WA, with the heaviest rain expected to occur from the southwest coast up to just north of Perth. Image: Forecast accumulated rain over the next seven days, showing how much rain this week’s front is expected to deliver. Fresh to strong winds will also blow across the southern half of WA on Friday and Saturday. While these won’t be anywhere near as strong as a typical mid-winter cold front, damaging wind gusts are possible in exposed areas along state’s southwest coast. Image: Forecast wind gusts on Saturday morning. Severe weather warnings may be issued in the coming days as this cold front approaches and crosses southwestern Australia. Check the latest forecasts and warnings for the most up-to-date information in your area.

29 Apr 2025, 2:20AM UTC

Australia's primary climate drivers are currently in a neutral phase, which means the weather around Australia is likely to be dominated by more local effects heading into winter. Pacific Ocean climate driver The El Niño Southern Oscillation (ENSO) has returned to a truer neutral phase, after trending towards a La Niña-like phase during summer. Sea Surface Temperatures (SST) across the central equatorial Pacific Ocean, in a region denoted as Niño3.4, can be seen returning closer to average in the image below, after trending colder than average during summer. Image: Sea Surface Temperatures across the Pacific Ocean on April 27, 2025. Source: NOAA. The La Niña signal was enough for the US’s Climate Prediction Center (CPC) to declare a La Niña event last January – but was not sustained enough for the Australian Bureau of Meteorology to follow suit, with a different set of thresholds. The CPC did declare the end of the La Niña event in mid-April, with the ENSO returning to neutral. Image: Niño3.4 Sea Surface Temperature Index over the past 5 years. The weak La Niña signal did influence the weather over Australia, especially over the east, bringing Queensland’s third wettest March on record. The ENSO is forecast to remain neutral (neither La Niña or El Niño) over the coming winter, limiting its impact on Australia’s weather. Indian Ocean climate driver The Indian Ocean Dipole (IOD) has remained in a neutral phase over the past few months. A negative IOD occurs when warmer than average SST lie to the northwest of Australia, and cooler than average waters extend over the western Indian Ocean, near the Horn of Africa. The warm waters near Australia promote increased rainfall, especially over the north and interior. A positive IOD sees the reverse, with cooler waters sitting near Australia, and a reduction in rainfall moving east and south over the country. Image: Sea Surface Temperatures across the Indian Ocean on April 27, 2025. Source: NOAA. The IOD is expected to remain neutral over the coming winter, but early indications hint towards warming oceans off Indonesia and northwest Australia during the late winter and spring period. These warm waters come through the Indonesian Throughflow as water moves from the Pacific Basin to the Indian Ocean bringing increased chances of a negative IOD developing later this year. Southern Annular Mode (SAM) The SAM modulates the northwards extent of the westerly belt over the Southern Ocean. In a negative phase, the SAM promotes cold fronts further north over Australia, bringing increased rainfall to southern Australia. The SAM has however seen strong periods of the positive phase over recent months, promoting block high pressure patterns over southern Australia, keeping cold fronts well to the south. Image: Annotated mean sea level pressure anomaly for the first three months of 2025. Source: ClimateReanalyzer The blocking high pattern has maintained severe rainfall deficiencies over South Australia, Victoria and Tasmania, while promoting increased onshore flow and rainfall over eastern Australia. Image: Rainfall deficiencies in Australia from February 1 2024 to 31 March 2025. Source: BoM. READ MORE: Adelaide's driest start to the year since the 1980s Warm temperatures have also been maintained over the southeast of the country. Adelaide, Melbourne, Canberra and Sydney are each running around 3°C above the long term average maximum temperature for April. Looking at the pressure anomaly map below, higher than average pressure over Australia’s southeast is expected to persist through May and the start of winter, signalling a continuation of this positive SAM tendency. This could prolong the rainfall deficiencies plaguing southern Australia during what is usually the wettest months of the year – a bad sign for water supply and the agriculture sector. Image: Sea Level Pressure anomalies for June 2025. Warm Sea Surface Temperatures (SST) around Australia The map below shows a continuation of the extremely warm SST anomalies all around Australia over the past months. Image: Above average SST surrounding Australia on April 27, 2025. Source: BoM. The increased atmospheric moisture available due to these very warm SST has promoted above average rainfall over northern and eastern Australia in the past few months. A continuation of these warm waters should maintain above average rainfall across eastern Australia, potentially also over Western Australia as more fronts may cross into the west. Southern Australia would be primed for increased rainfall, however the lack of frontal passages picking up this moisture should limit this potential – for now. Overall, seas around Australia are expected to remain much warmer than average in the coming months, fuelling thunderstorms and heavy rainfall events well into this year. What to expect this winter In the absence of any climate drivers in the Pacific and Indian Oceans, Australia's weather will be more strongly influenced by the SAM and local sea surface temperatures in the coming months. Higher than normal mean sea level pressure to the south of Australia could continue to cause drier-than-average weather across already parched areas of southern Australia this winter. By contrast, abnormally warm seas could promote above average rainfall in parts of eastern and western Australia. Image: Sea Level Pressure anomalies for July 2025. Image: Monthly precipitation anomalies for July 2025. Temperatures are expected to be warmer than average for most of Australia in the coming months, although increased cloud cover might help suppress daytime warmth in parts of Queensland and northern NSW. Image: Monthly maximum temperature anomalies for July 2025.