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NOAA: El Niño is ‘significant and strengthening,’ could rival strongest on record

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A new forecast from NOAA says this El Niño is “significant and strengthening,” with the potential to become very strong — even rivaling the strongest on record.

This is the strongest forecast NOAA has issued so far this year.

In order for El Niño to be classified as “very strong,” the temperature in the tropical Pacific Ocean needs to be running at least 2 degrees Celsius warmer than average for at least three months in a row. That can be a difficult hurdle to jump, and it’s only happened twice since meteorologists started to monitor conditions in the tropical Pacific: the winters of 1982-1983 and 1997-1998.

As of early August, this year is running neck and neck with the record 1997-1998 season, and NOAA forecasters are confident we will see an increase in tropical Pacific ocean temperature that would push this El Niño event into at least the “strong” category, potentially reaching or even exceeding the 2-degree “very strong” criteria.

[It’s hurricane season, but where are all the hurricanes?]

NOAA forecasters say there’s a 90 percent chance that El Niño will continue through the winter months, and an 85 percent chance (up from 80 in July) that it will last into early spring next year. Looking at the models, oceans temperatures and atmospheric patterns, NOAA says they see a “significant and strengthening El Niño.”

What does this mean for winter?

In the West, a very strong El Niño would greatly increase the chances for torrential rain storms this winter — something that drought-stricken California direly needs, though these storms come with a cost. The 1997-1998 super El Niño brought widespread flooding and landslides that killed 17 people and caused more than half a billion dollars in damage, according to the Los Angeles Times.

[A side-by-side El Niño comparison of 1997 and 2015]

Even if this winter delivers a super El Niño, it probably still won’t be enough to end the drought. As of this week, anywhere from 12 to 20 inches of rain is needed over the course of six months in order to squash the drought in California’s Central Valley.

In the Mid-Atlantic, results have been a mixed bag, and highly dependent on El Niño’s final strength. Moderate or strong El Niños could potentially deliver a very white winter, while a very strong El Niño could mean conditions too warm for snow in the Mid-Atlantic.

“El Niño events have had a remarkably varied history in our region when it comes to snowfall,” said Matt Rogers in an early winter outlook. “Our most recent El Niño event (2009-2010), a moderate one, gave us the snowiest winter on record (56.1 inches), while the strongest one (1997-1998) was very warm and only delivered 0.1 inches the entire season, our least snowy outcome!!”

[Will this El Niño bust or bolster D.C.’s snow prospects?]

But El Niño is not the only game in town, and the winter outcome will highly depend on what else is going on across the Northern Hemisphere. For example, as of July, the North Atlantic Oscillation, which meteorologists use to measure the strength and location of the jet stream during wintertime, was running very negative. Historically, this pattern has continued into the winter months and means the Eastern United States could have plenty of cold air to play with come December.

Combine a few Arctic blasts (polar vortex, anyone?) with ample moisture from a very strong El Niño pattern and we might be looking at a gangbuster, snowy winter. Even more so if El Niño ends up being slightly weaker than predicted.

More El Niño:

How the 1982-1983 super El Niño kept itself a secret

Why this El Niño could still be a bust for California drought relief

From July: El Niño intensifying, could rival strongest in recorded history