Based on a key measurement, this year’s extreme El Niño has surpassed the 1997-1998 phenomenon, making it now the strongest ever recorded.
That could mean abnormal weather for all of North America, including big snow in the Southwest, torrential rain in Southern California, and a drier-than-normal winter in the Northeast. Urban areas like Los Angeles are already prepping on how to handle the monster El Niño, with city agencies warning of flooding, mudslides, and lots of rain. Here’s what you need to know about how this latest development will influence winter across the United States.
El Niño occurs when ocean water temperatures in the central Pacific Ocean become warmer than normal. While this may not sound like a big deal, it can have profound impacts on weather patterns around the world and it can create very severe weather.
The US National Oceanic and Atmospheric Administration (NOAA) continually monitors the warmth of the water in the central Pacific as one major indicator of an El Niño’s strength. In mid-November, the recorded temperature was the highest ever seen in the region.
Source: NOAA via the New Scientist
The New Scientist reports that during 1997’s El Niño, the central Pacific’s temperature peaked at 2.8°C above average. This year, temperatures reached 2.8°C on November 4 and then rose to 3.1°C on November 18. As of December 2, the central Pacific was still at about 2.9°C above average.
According to Axel Timmerman at the University of Hawaii in Honolulu, the temperatures in the central Pacific have the biggest impact on global weather during an El Niño year. Since 1950, there have been only two other El Niño winters of similar magnitude, one in 1982-1983 and another in 1997-1998. The 1997-1998 event caused flooding in the southeast, a severe ice storm in the northeast, $550 million in rain and flood damages in California, and tornadoes in Florida. Overall, the last strong El Niño resulted in $35 billion in damage and 23,000 deaths worldwide.