Impacts unclear, though Gulf Coast could see rain surplus
NOAA’s El Niño map shows widespread above-average sea surface temperatures.
Staff Report
FRISCO — A long overdue El Niño once anticipated as a potential drought-buster for California has emerged, but may not have a huge impact on North American weather.
Forecasters with NOAA’s Climate Prediction Center made the announcement this week after measuring ocean surface temperatures in the Pacific. Those temps have been running above average for several months but just now crossed the El Niño threshold. the climate experts said in their monthly outlook.
El Niño, the warm phase of an irregular Pacific Ocean cycle, can have huge impacts globally, shifting storm tracks, raising temperatures and even leading to drought in other parts of the world.
For Colorado, the effects are nuanced, but the recent storm pattern that favored the southwestern mountains is a classic sign of El Niño. Similarly, the pattern can bring copious rain and snow to California, but it’s unclear whether the current edition will pack enough of a punch to make a difference for the drought-stricken state.
The map above shows at least part of the cause for the sustained California drought, as extremely warm ocean temps off the West Coast have pumped up a ridge of high pressure that blocks storms.
Some impacts often associated with El Niño may appear this spring in parts of the Northern Hemisphere, such as wetter-than-normal conditions along the U.S. Gulf Coast.
“Based on the persistent observations of above-average sea surface temperatures across the western and central equatorial Pacific Ocean and consistent pattern of sea level pressure, we can now say that El Niño is here,” said Mike Halpert, deputy director, NOAA’s Climate Prediction Center, and ENSO forecaster. “Many climate prediction models show this weak El Niño continuing into summer.”
Forecasters say it is likely (50 to 60 percent chance) that El Niño conditions will continue through the summer.
The last El Niño, in 2009-2010, was a moderate to strong event. Other recent El Niño’s took place from 2002-2003 (moderate), 2004-2005 (weak), 2006-2007 (weak to moderate). The last very strong El Nino was 1997-1998 and was known for providing heavy rainfall in the West, especially California. As for this year, “this El Nino is likely too late and too weak to provide much relief for drought-stricken California,” added Halpert.
