U.s. Weather

El Niño has developed in the tropical Pacific, and NOAA says it could intensify into a moderate or strong event this fall. That matters because this warm phase of the ENSO cycle can shift weather patterns far beyond the Pacific Ocean. The agency’s latest advisory says there is a 63% chance that sea surface temperatures in the eastern Central Pacific will rise more than 2 degrees Celsius above the neutral threshold. NOAA says that would qualify as a “very strong” El Niño. Why Forecasters Are Paying Close Attention El Niño is part of a natural climate oscillation known as ENSO, which reflects changes in winds, temperature, and pressure across the Pacific. NOAA and other experts rely on satellite, ocean, and atmospheric observations to track it, because the event can affect agriculture, energy, national security, and other sectors. As www.forbes.com reported in its coverage of the advisory, some climate experts had warned that it was too early to be certain about the event’s strength. Even so, the latest outlook points toward a stronger setup than many had expected. What It Could Mean For Weather According to NOAA, typical U.S. impacts include a less active Atlantic hurricane season because of stronger upper-level winds. At the same time, storm development often increases in the central and eastern Pacific basins. Other common effects include stormier conditions across the southern tier of the country. NOAA also says El Niño can increase the likelihood of high tide flooding and harmful algal blooms, especially along the West Coast. Outside the U.S., the pattern can bring heavy rain and snow to dry regions of Peru, Chile, Mexico, and the southwestern United States. It can also push wetter regions such as the Brazilian Amazon and the northeastern United States into months-long droughts. A Pattern With A Heavy Track Record NASA notes that strong El Niño events have disrupted agriculture, fishing, and other ecosystem services. The agency also points to past super El Niños in 1982-1983, 1997-1998, and 2015-2016. Climate analysts cited by www.forbes.com said model ensembles were already leaning toward moderate or strong El Niño conditions by mid-June, with some October projections showing the event could push into super-El Niño territory. For now, the key question is how far the warming goes from here. That is why this latest advisory is drawing so much attention. El Niño is here, and the coming months will show whether it remains strong or becomes one of the most powerful events in recent memory. Read more at: www.forbes.com

El Niño Is Back, And It Could Shape Weather Across The U.S. This Year