Australia's unseasonably warm winter 2026, heavy rain, and El Niño impacts
Consensus Summary
Australia is experiencing an unusually warm winter in 2026, with multiple cities breaking June temperature records. Sydney, Melbourne, and Hobart have recorded their warmest starts to winter, driven by a strong positive Southern Annular Mode (SAM) phase and shifting atmospheric patterns. The SAM index reached +4.41, its highest value since May 2023, pushing westerly winds south and preventing cold fronts from reaching the continent. This has resulted in unseasonably warm temperatures, with Sydney’s mean June temperature at 16.3°C, 3°C above average. Meanwhile, the ski season in the alpine regions has been poor, with no natural snow cover by July for the first time since 2015. Despite the warmth, Australia has also seen heavy rainfall, with the first six months of 2026 marking the wettest start to an El Niño year on record. Forecasts predict another round of significant rain across eastern and southern states, including 25 to 50mm for Victoria, NSW, and Tasmania, with isolated areas potentially receiving 100mm. The Guardian also highlights global trends, noting that the UK recorded its hottest June day on 26 June 2026, with temperatures reaching 37.3°C, reflecting broader climate extremes. While the SAM index may drop soon, bringing colder weather, the long-term outlook suggests continued dry conditions in late winter and spring, raising concerns about drought and bushfire risks for the upcoming summer.
✓ Verified by 2+ sources
Key details reported by multiple sources:
- Sydney recorded its warmest June on record, with a mean temperature of 16.3°C (3°C above average).
- Melbourne’s June temperatures were about 3°C above normal, on track for its warmest June since 1957.
- Hobart’s June was the mildest since at least 2002.
- The Southern Annular Mode (SAM) index reached +4.41 this week, the highest value since May 2023.
- Australia’s national average rainfall for the first six months of 2026 is just below 400mm, about 100mm above the long-term mean.
- 2026 is the wettest start to an El Niño year on record for Australia since 1900.
- The ski season in Australia’s alpine slopes is off to a poor start, with no natural snow cover by July for the first time since 2015.
- The positive SAM phase has shifted westerly winds south, preventing cold fronts from reaching Australia.
- Widespread rain of 25 to 50mm is forecast for Victoria, NSW, and Tasmania in the coming week, with isolated pockets of 100mm possible.
- The UK recorded its hottest June day on 26 June 2026, with temperatures reaching 37.3°C (previously 36.1°C in 1976).
Points of Difference
Details reported by only one source:
- The only previous years in the Snowy Hydro snow dataset with no snow by July were 1967 and 1957.
- Sydney is predicted to hit 23°C on Thursday (6°C above the July average), and Brisbane 25°C (4°C above average).
- Canberra’s overnight minimums are forecast to reach 7°C (7°C above normal).
- The Murray-Darling Basin is expected to receive widespread falls of 25 to 50mm, with pockets of 100mm possible.
- The SAM index is expected to drop this week, paving the way for colder weather and potential snow in the Alps by next weekend.
- Adelaide recorded above-average June temperatures in its first three weeks.
- Perth is the only southern capital with typical June temperatures.
- Melbourne’s dam levels are at 64% and falling, the lowest since the 2017–19 drought.
- The Tasman Sea high-pressure systems are directing warm, humid air over southeast Australia, raising minimum temperatures.
- The southern hemisphere jet streams have shifted poleward, causing more high-pressure systems over southern Australia.
Contradictions
Conflicting information between sources:
- The Guardian states Perth is the only southern capital with typical June temperatures, while ABC does not mention Perth’s temperatures at all.
- ABC reports Sydney’s mean June temperature is 16.3°C, while Guardian does not provide an exact figure but confirms it is the warmest start to winter on record.
- ABC notes that the SAM index soared to +4.41 this week, while Guardian does not specify the exact value but confirms it is in an extreme positive phase.
Source Articles
Heavy rain to soak Australia's east as un-El Niño-like weather continues
For an El Niño year, 2026 is so far the wettest on record for Australia, and an influx of tropical moisture is about to deliver another round of widespread rain.
Australia’s next summer isn’t guaranteed to be the hottest yet – but it’s looking likely | Milton Speer and Lance M Leslie
A warm start to winter is part of a global trend of extreme and unseasonable temperatures caused by global heating Many parts of Australia have already broken early winter maximum and minimum temperature records. In southern Australia, Sydney and Melbourne had their warmest-ever starts to winter. Daily observations show both cities experienced above-average June temperatures almost every day of the month. Continue reading...