El Niño is all the rage in the weather world, and it will continue to be in the fall and winter months ahead.
And with good reason...
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What is El Niño?
We've written about this several times before, so here's a refresher.
El Niño refers to warmer-than-average waters in a very specific part of the equatorial Pacific.
It's nothing new. In fact, this is something that's been monitored for centuries by fishermen/mariners in places like Peru.
(La Niña is the opposite - cooler than average waters in the equatorial Pacific.)
We care about El Niño and its counterpart, because they play a big role on global weather patterns.
El Niño, in particular, leads to a reduction in Atlantic tropical systems but a more active storm track in the Southern U.S.
This fall and winter's El Niño is forecast to be the warmest on record, according to the National Oceanic and Atmospheric Administration.
There are models that actually show an even stronger El Niño than what NOAA has currently forecast.
What makes El Niño "strong?"
A "strong" El Niño is when the ocean temperatures within this region are 1.4°C to 1.9°C above average. It's "very strong" when that anomaly is 2.0°C or higher.
Since 1950, there have been eleven weak, seven moderate, three strong and four very strong El Niño falls and winters.
When trying to draw conclusions about the upcoming fall and winter, we're working with an admittedly small sample size.
What's happened in the past during strong and very strong El Niño?
The winter predictions have already begun on various social platforms, and they may be a bit premature.
There are other factors (aside from El Niño) that drive a winter forecast, such as preceding tropical activity, solar activity and Siberian snow cover.
For now, let's look at the past.
The 30-year average snow total from 1991-2020 in the Triangle is 7.9." That number has been a lot lower in the last five-to-ten years.
Notice how there's a lot of variation in average snow during weak, moderate, strong and very strong El Niño winters.
That can be traced back to the small sample size that we're dealing with.
When looking back at the five strongest El Niño winters, you can see the variation in snow totals.
The winter of 1982 and 1983 was very snowy, whereas the other four weren't. Yet a strong El Niño (1.4°C to 1.9°C above average) often yielded high snow totals.
The thing to remember about winter in North Carolina - it's still more likely that you'll see rain than snow.
So, I looked at all precipitation in El Niño falls and winters.
Most El Niño falls and winters had precipitation totals near the 30-year average, but very strong El Niño falls and winters gave us above-average total precipitation.
One could infer - from that alone - that we'll transition to a wetter weather pattern overall in the coming months.
That would be welcomed news for an area that is still battling drought.