The odds have risen that a strong, weather-changing El Nino will last at least until early spring, and it may be one of the strongest in the 65 years of records, the Climate Prediction Center said.
Sea-surface temperatures, one measure of an El Nino, increased across parts of the equatorial Pacific, the College Park, Maryland-based center said in a statement Thursday. There is an 85 percent chance the phenomenon will last into the February to April period, up from 80 percent in July. It may not make itself felt in the U.S. until this summer ends.
“We’re predicting that this El Nino could be one of the strongest El Ninos in the historical record going back to 1950,” said Mike Halpert, deputy director of the climate center.
Forecast models predict El Nino will peak sometime in the Northern Hemisphere’s late fall or early winter. Temperatures in parts of the Pacific may be close to 2 degrees Celsius (3.6 Fahrenheit) above normal, the agency said.
“It could reach or exceed 2 degrees Celsius, a value we have only recorded three times in the last 65 years,” Halpert said on a conference call with reporters.
Current sea surface temperatures are the second-warmest recorded in July and exceeded only by 1997, when the most powerful El Nino on record began. Surface temperatures in the Pacific reached 2.3 degrees above normal in 1998.
Halpert cautioned the El Nino could fade.
“Just because something is favored doesn’t mean it is guaranteed to happen,” he said.
The phenomenon occurs when parts of the Pacific Ocean warm above normal, triggering a corresponding reaction in the atmosphere. El Ninos are known to diminish the hurricane threat in the Atlantic and cause stormier winters in the southern U.S. They can also threaten grain crops in Asia and Central America and crimp global rice production.
In addition, El Ninos can shift the U.S. winter storm track into the southern part of the country, raising the possibility of more precipitation in California, a state suffering under a four-year drought.
While there may be more rain and snow in California, it isn’t likely to be enough to end the drought, said Kevin Werner, director of the National Oceanic and Atmospheric Administration’s western region climate services.
It would take 2.5 to 3 times the normal amount of rain to make up California’s current water deficit, Werner said. The state’s wettest year on record only produced 1.9 times the normal amount.
“A single El Nino year is unlikely to erase four years of drought in California,” Werner said on the conference call.