El Niño's waters are the hottest ever measured. They're getting hotter.

Sea surface temperatures just hit a record high in a 2.4-million square mile region of the deep Pacific Ocean known as Niño 3.4, the key area scientists are tracking to measure the rapidly strengthening El Niño.
The daily average temperature – 85.73 degrees – on Sept. 29 was higher than at any other time on record in the region, according to preliminary data from the National Oceanic and Atmospheric Administration. It continued to climb the next day.
The temperature is