El Niño has strengthened to what some scientists call "unprecedented levels," weeks before its expected peak in December, BBC Weather reported. Australia's Bureau of Meteorology said average weekly sea temperatures in the central Pacific have reached their highest level on record.

The bureau's weekly data only goes back to 2008, the BBC noted. But it now exceeds levels seen during the record-breaking December of 2015. Temperatures above 30C have also been recorded for the first time in parts of the tropical Pacific.

The new reading follows an earlier record in September. The Guardian reported then that the temperature rise at the heart of El Niño had reached 3.05C, above the 3.02C set in late November 2015. Climate scientist Zeke Hausfather called the forecasts "mind-blowing," The Guardian reported.

"We are currently witnessing an El Niño event that is unprecedented in the historical record," Hausfather told the BBC. He said the warmth "is spilling out of the traditional El Niño region."

El Niño is a natural pattern that happens about every two to seven years, the BBC reported. It releases extra heat from the oceans into the air. Combined with human-driven climate change, that heat is expected to help make 2026 one of the warmest years on record, with high temperatures likely to continue into 2027.

The World Meteorological Organization says there is no proof yet that climate change makes El Niño stronger or more frequent, the BBC reported. That remains an active area of research.

The effects are already being felt. The Guardian reported record wildfires in Indonesia, weaker monsoon rains in India and drought in Central America. Strong El Niño years also tend to mean fewer Atlantic hurricanes and more storms in parts of the Pacific, the BBC said.

What we know: El Niño has broken weekly ocean temperature records and is still strengthening.
What we don't: How strong it will be at its peak, and which regions will be hit hardest this winter.