Right now south-eastern Australia is having an unbearable summer. Temperatures in Sydney have regularly been in the upper 30s in recent weeks, while inland areas have had several days in the mid-40s.

January was the hottest month on record for Sydney since 1859, and the persistent warmth into February (with many places topping 35C day after day) may topple the New South Wales record of 50 hot days in a row.

Firefighters have been on high-alert, sporting events have had to be cancelled and power stations have struggled to cope with the high demand as air conditioning systems run at full tilt.

But it isn’t just Australia that is feeling the heat. Climate scientists have confirmed that January 2017 was the third warmest January in 137 years of record keeping. Which is shocking given that it occurred during a La Niña event. We expect global temperature records to be broken during El Niño events (when central and eastern Pacific waters are warmer than average) but until now El Niño’s cooler cousin, La Niña, has usually brought respite from the heat.

Last year we had the extreme “Godzilla” El Niño, contributing to record breaking weather conditions all around the world. Meanwhile, in recent months we’ve seen weak La Niña conditions. Now the US National Oceanic and Atmospheric Administration have confirmed that La Niña has slipped away and some climate models are hinting that El Niño conditions could return as early as this summer.

There is still a fair bit of uncertainty, but if El Niño does roar back this quickly we’d better brace ourselves for yet more record breaking weather.