These nations are in the hot seat.

An alarming map from the Climate Impact Lab shows where Super El Niño will cause the most additional heat deaths as the weather anomaly gains steam in the Pacific.

According to the apocalyptic cartography, dubbed the El Niño Heat Mortality Tracker, over 373,000 additional people will perish between October 2026-March 2026 with Nigeria, India and Brazil accounting for a third of the death toll.

This comes as the anomalous weather system — measured by sea surface temperatures — propelled water temps in the Niño 3.4 region of the East-Central Pacific to record 3.4 C (over 6 F) warmer than normal for the week of October 18-24.

The phenomenon could send temps soaring to more than six times that of a typical El Niño between November and January, according to the World Meteorological Organization.

To determine just how devastating the effects will be, the team estimated the number of additional heat deaths caused by the current El Niño compared with average conditions from 1996 to 2005. The study spans roughly 3,700 regions worldwide and is updated monthly with forecasts for the next six months.

Per the map, El Niño will contribute to 857,400 additional heat-related deaths from the phenomenon’s start in June 2026 to March 2027 — over 350,000 higher than the scientists’ projection just a month ago.

Of the nine-month total, over half that many additional deaths are expected to occur over the next six months.

Nigeria is predicted to bear the brunt of the burn, with over 56,000 projected heat-related casualties during this timeframe.

Following close behind, per the model, is India, where 55,200 are expected to be at risk.

Rounding out the top five are Indonesia (29,300), Brazil (19,500) and Sudan (14,700).

Using this map, researchers will be able to estimate where the phenomenon is most severe and how governments can respond to mitigate the damage.

“Our research puts new forecasting capabilities to work to answer one of the most urgent questions we face: where is extreme heat likely to cost lives?” said Michael Greenstone, a co-founder of the Climate Impact Lab and the Milton Friedman Distinguished Service Professor in Economics at the University of Chicago. “Being able to anticipate the deadly effects of extreme heat is a major step forward.”

He added, “It means we can identify where people face the greatest risks and give decision-makers a chance to act before lives are lost.”

Researchers estimate that El Niño has caused 484,500 additional deaths since June.

Some of the ripple effects have included wildfires in Indonesia, the absence of crucial monsoon rains in India, and droughts in Central America.

Stateside, meanwhile, the Western and Southern US are expected to be battered by more storms and rain while New York is slated to emerge shockingly unscathed.

El Niño could cause the Big Apple to feel like autumn into January — with up to a quarter less snow forecast this winter than last, AccuWeather Senior Meteorologist Matt Benz previously told The Post.