Australian Weather

21 Aug 2026, 7:41AM UTC

Satellites have captured changes in marine life directly associated with a rapidly strengthening El Niño in the tropical Pacific Ocean. The typical weather impacts of El Niño are widely known across the world – they include reduced rainfall in Australia, suppressed hurricane activity in the Atlantic, a weaker monsoon in India and heavier rain in some western areas of South America. In addition to these atmospheric anomalies, El Niño events also cause large-scale changes to ocean currents and water temperatures across the Pacific Ocean, and these changes can have massive impacts on marine life. Very strong El Niño getting stronger El Niño developed in the middle of 2026 and has been strengthening rapidly in the last couple of months. By the middle of August, sea surface temperatures in the central tropical Pacific Ocean – a key monitoring region for El Niño – were more than 2.7°C above the 1991-2020 average. These are some of the highest anomalies on record for the central Pacific.   Image: Sea surface temperature in the Niño3.4 region (central equatorial Pacific Ocean) from 1981 to 2026. The dark red line is 2026, showing current temperatures are the highest on record for this dataset. Source: ClimateReanalyzer.org. Computer models predict that this El Niño will continue to strengthen in the coming months and is likely to peak at record-breaking strength towards the end of 2026. Based on its forecast strength, El Niño will likely persist through the first few months of 2027. The Bureau of Meteorology’s ACCESS-S model anticipates that the monthly relative temperature anomaly – which accounts for climate change – in the central tropical Pacific Ocean will reach around +3.6°C in November 2026. This would easily beat the previous record of +2.65 from November 1902, according to Bureau data dating back to 1900. This very strong El Niño event will have far-reaching impacts on marine life across the Pacific, and some of these impacts are already starting to occur. Marine food web responding to El Niño NASA’s PACE satellite has detected suppressed phytoplankton abundance in the central Pacific Ocean in response to this year’s El Niño. The satellite detected a relative drop in chlorophyll-a concentrations – the pigment present in most phytoplankton – during June this year compared to June last year. Phytoplankton abundance is directly linked to nutrient availability. When El Niño is underway, equatorial trade winds weaken or reverse over the tropical Pacific. This causes warm water to build near the surface of the central and eastern tropical Pacific, suppressing the upwelling of cooler, nutrient-rich water.   Image: Concentrations of chlorophyll-a in the equatorial Pacific Ocean in June 2025 (left) and June 2026 (right). The presence of El Niño in 2026 has caused a reduction in chlorophyll-a concentrations in parts of the Pacific Ocean. Source: NASA Earth Observatory / Michala Garrison. Phytoplankton are important because they produce oxygen and feed other organisms. While microscopic, these tiny plant-like organisms play a critical at the foundation of marine food webs. For example, phytoplankton feed small marine animals called zooplankton, which feed larger fish, whales and other marine life. Peru’s anchovy fishing operations – which produce around 20% of the world’s fishmeal and fish oil production – are also sensitive to El Niño. Past El Niño events have caused significant declines in fish numbers near Peru because of warm surface water and suppressed upwelling in the eastern tropical Pacific. Fishing operations in Peru have been suspended in recent months due to this year’s developing El Niño. Earlier this month, the Peruvian Ministry of Production (PRODUCE) carried out operations to obtain information about the state of anchovy and other open-water resources near Peru. According to reports, this assessment found that anchovy shows relatively good growth and reproductive activity in Peruvian waters, despite the developing El Niño. This information offers some hope that operations can resume sustainably, even as El Niño continues to strengthen. Sea birds can also be impacted by disruptions to marine food webs driven by El Niño. Last month, there were reports of pelicans flocking to Peruvian ports to find food as fish stocks declined offshore. Coral bleaching also has close links with El Niño’s ocean warmth. According to forecasts from NOAA’s National Weather Service, there is a 90% likelihood of coral bleaching across a broad area of the central and eastern tropical Pacific Ocean in the next 4 months. This region closely matches the warm water footprint of El Niño.   Image: Probability of coral bleaching in the next four months. Source: NOAA. This El Niño event will continue to have far-reaching impacts across the world during the rest of 2026 and early in 2027.

20 Aug 2026, 6:08AM UTC

A vast northwest cloudband stretching from the Indian Ocean to the Tasman Sea is delivering steady rainfall to parts of Australia, especially to inland parts of the east. This train of moisture extending thousands of kilometres across the continent has its origins in tropical waters off the northwest of Australia. READ MORE: What is a northwest cloudband? Rain is also falling where its least wanted in mid-August – namely in the mainland alpine region where the snowpack at the ski resorts is taking a beating. The rain could turn to snow at higher elevations overnight, but no significant accumulation is expected. Image: Precipitable water and mean sea level pressure across Australia at 4 am (AEST) on Thursday, August 20, 2026, with atmospheric water vapour indicated by blue shading. Source: Weatherzone. How much rain has fallen so far? The combined radar and satellite loop (below) doesn’t show all the rain that is falling this Thursday, due to a lack of radar towers in remote parts of the inland. READ MORE: How to read weather radar images (and why it matters) But falls of around 10 mm have been recorded in outback SA and far western NSW between 9 am and 3 pm this Thursday, with rain continuing in many areas. Image: Three-hour combined radar and satellite loop from midday to 3 pm (AEST) on Thursday, August 20, 2026. Source: Weatherzone. In the 24 hours to 9 am Thursday, heavy falls were recorded at multiple locations from this persistent system. Notable readings included: 118 mm at Lake Mackenzie in northern Tasmania (we wrote on Tuesday that northwest Tas was in line for the heaviest falls in this system) Widespread falls exceeding 25 mm in central Victoria in a belt north of Melbourne but south of the Murray River. The heaviest Vic total was 43 mm at Daylesford in the Central Highlands, while the alpine resorts of Mt Hotham (40.8 mm) and Falls Creek (38.6 mm) were not far behind. 25.6 mm fell at Thredbo Top Station, which was the heaviest NSW total. When will the rain clear? The inland rain should start to ease on Friday with a mostly dry weekend in store, although showers should persist until the middle of next week on parts of Victoria’s coastal fringe. Forecast models currently suggest that the inland can expect another drenching early next week as a low pressure system crosses southeastern Australia. Similar to this week’s system, there will be no influx of cold Southern Ocean air to accompany the rainfall, although chilly air could push across the southeast at the back end of the system around Wednesday next week, potentially producing light snowfalls.