El Nino Forms, Expected To Strengthen, Say NOAA Forecasters
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By noaa.gov, noaa.gov.
NOAA’s National Weather Service announced today that El Nino has developed in the tropical Pacific, and issued an El Nino Advisory. El Nino, the warm phase of the El Nino Southern Oscillation (ENSO), is predicted to intensify to a moderate or strong level this fall. Forecasters predict a 63% chance of sea surface temperatures exceeding 2.0°C in the Nino-monitored region of the Pacific. If this threshold is surpassed, NOAA considers the event a “very strong” El Nino.
What is El Nino?
NOAA declares an El Nino (Spanish for “little boy”) has formed when temperatures in the equatorial Pacific are 0.5°C above average for several consecutive months. Additionally, NOAA monitors the atmosphere above this region of the Pacific, looking for a pattern called the Walker Circulation, a massive east-to-west air flow driven by the temperature and pressure differences between the warm western and cool eastern oceans. When the Walker Circulation breaks down and warmer water shifts east toward South America, El Nino is declared.
What does El Nino mean for U.S. weather?
El Nino tends to be strongest during the winter months, and its global impacts are typically most significant in the northern hemisphere winter. During a typical El Nino winter, the jet stream over the north Pacific Ocean tends to shift southward, bringing the storm track over the southern tier of the U.S. The southward shift in the storm track also leads to drier conditions over the Northern Rockies and Ohio and Tennessee valleys. For temperatures, El Nino often leads to a warmer than usual winter over the northern U.S.
Read the full article here: El Nino forms, expected to strengthen, say NOAA forecasters
Originally published on 11 June, 2026.
