No El Nino this Fall
COLLEGE PARK, MARYLAND
August 10, 2017
• Latest estimates virtually rule it out
• “Overall, the ocean and atmosphere system remains consistent with ENSO-neutral”
Whatever these days passes for a “normal” winter seems to be in store for California this year, based on the new El Nino forecast from the National Weather Service’s Climate Prediction Center.
The experts say there’s about an 85 percent chance of no El Nino or La Nina weather impact through September, with the odds slowly decreasing to little better than a 55 percent chance during the December through February period.
The weather conditions called El Nino and La Nina can bring copious amounts of rain and snow to California – or prompt exceedingly dry winters.
Equatorial sea surface temperatures (SSTs) were near average across most of the Pacific Ocean in July. It’s a combination of warmer than normal water temperatures plus certain wind patters that can result in either an El Nino event or a La Nina.
The latest weekly Niño SST index values were close to zero in all four Niño regions, having recently decreased from higher levels in some regions. The upper-ocean heat content anomaly was near average during July, the report says.
“Overall, the ocean and atmosphere system remains consistent with ENSO-neutral,” the report says.
The majority of computer models favor ENSO-neutral through the remainder of 2017. These predictions, along with the demise of the recent Pacific warmth and continued near-average atmospheric conditions over the Pacific, lead forecasters to favor ENSO-neutral through the winter.
However, some chance for El Niño (15 percent to 20 percent) or La Niña (25 percent to 30 percent) remains during the winter, the forecasters say.