The World Meteorological Organization said late last week that El Nino has passed its peak based on specific temperature, wind, and atmospheric pressure conditions.
That's technically true, but Michelle L'Heureux, lead El Nino forecaster for the National Oceanic and Atmospheric Administration's Climate Prediction Center, said there's a few months lag time before the changes affect the Americas.
El Nino is the occasional but natural warming of the central tropical Pacific which, along with changes in the atmosphere, alters weather patterns worldwide. It often brings more rain to California and parts of the U.S. West and South, raises temperatures globally a bit, and causes droughts elsewhere in the world. In Canada, a balmy November and December in many parts of the country have been linked to this year's super El Nino bringing warm air from the Pacific.
In December and January, El Nino measurements showed it tied 1997-1998 for the strongest since records started being kept in 1950.
El Nino-like conditions into May
"It's still strong, but it has reached a peak value and it's starting its decline," said University of Oklahoma meteorology professor Jason Furtado. "It's still there; it's not like we don't have El Nino anymore. We can still expect (El Nino) like conditions in March and April and even into May, as well."
Mike Halpert, deputy director of the climate prediction centre, said this El Nino hasn't brought drought-struck California as much moisture as previous strong El Ninos, but there are still two months to go to get significant rainfall.
With El Nino still kicking, NOAA forecast a spring that's wetter than normal throughout the U.S. South, much of the West and part of the East. Only the Great Lakes region and Pacific Northwest are forecast to be dry. It also predicts warmer than usual weather along the entire West Coast and most of the country north of Colorado, Missouri and Tennessee, with only Texas, parts of Oklahoma and New Mexico cooler than normal.
Look out for La Nina
The International Research Institute at Columbia University forecast that once this El Nino fades, there's a 50 per cent chance it will be followed directly by El Nino's flip side, a La Nina. La Nina often means droughts in parts of the U.S. Great Plains and Southwest with more rain in the Northwest. La Ninas often mean warmer winters in the U.S. Southeast and cooler winters in the Northwest.
A 50% chance? That's really helpful!
In the slide above are the changes in sea surface temperatures over the past 4 weeks. El Nino/La Nina reveals itself along the equator between South America and Indonesia. The blue in the eastern half of that zone indicates that the SSTs are cooling which means El Nino is in decline.