La Niñaconditions are still expected to develop between August and October, however thetransition remains far from certain.
In itslatest diagnostic discussion,the National Oceanic and Atmospheric Administration offered a 55% to 60% chanceof La Niña developing during the fall and winter 2016-17, down from a 75% chancegiven in a May 12 discussion.
Definedby cooler sea-surface temperatures in the equatorial Pacific Ocean, a La Niña eventoften brings more supportive fundamentals for U.S. natural gas and electricity markets,including a higher probabilityof colder winters, hotter summers and increased tropical activity in the Atlanticbasin.
NOAAsaid that many models favor a La Niña event by the end of the Northern Hemispheresummer, continuing during fall and lasting into winter. However, compared to dynamicalmodels, the statistical models predict a later onset time in mid-fall and also predicta relatively weaker event.
"Theforecaster consensus is somewhat of a compromise between the two model types, favoringLa Niña onset during the August-October season, and predicting a weak event … ifan event were to form," the discussion states.
In ablog dated July 13, ColumbiaUniversity meteorologist Anthony Barnston echoed the uncertainty of any upcomingLa Niña event but still pointed to its likely formation by the end of the year.
"Duringthe last 60 or so years, strong El Niño years have often been followed by La Niñayears," Barnston wrote. "Although the record is short, it appears thestronger the El Niño, the greater the chance for a La Niña the next year. And wejust had a pretty strong El Niño!"
He notedthat the 55% to 60% chance of La Nina forming by the fall "is far from a surething" however "it means that getting some grade of La Niña, even if justa weak one, is more likely than not."