This is a look at our El Niño forecast from Columbia University. You’re looking at all the different computer model runs here, with those lines that kind of peak around September–October–November and then go down as we head toward February–March–April.
Notice that more than half of them are showing that this is going to be a very strong El Niño, which is a 2°C or greater sea surface temperature anomaly in certain parts of the equatorial Pacific Ocean.
But let’s look at the record — that’s 3.0°C — and there are even some model runs forecasting that as well. Either way, a very strong El Niño is certainly within the realm of possibility, and it’s virtually guaranteed that this will at least be a strong El Niño.
What Is El Niño?
El Niño is when you have warmer-than-average water temperatures across the equatorial Pacific Ocean, from roughly the coast of Peru in South America over to south of the Hawaiian Islands. You see a lot of those reds there in that circle.
How Does That Impact Our Weather?
In the next couple of months, it actually means fewer hurricanes. If you look at our hurricane forecasts from the National Hurricane Center or Colorado State University, you see fewer hurricanes due to stronger vertical wind shear (changes in wind direction and height) and greater trade winds. The stronger those east-to-west trade winds are, they can churn up the ocean and bring cooler water up to the surface — meaning again, fewer hurricanes.
Now, what does this mean for our winter?
We take a look at our Jersey Shore temperatures during the winter based on El Niño strength. Here’s one thing you notice: when you get to the strong and especially very strong categories, our temperatures get milder. There is a clear trend that as you move toward a stronger/very strong El Niño, you have a mild winter — particularly in the very strong case.
What About Snowfall?
We look at the snowfall anomaly (snow compared to average) at Atlantic City International Airport, which averages 17.4 inches. There’s a clear trend for a moderate El Niño to have a much snowier winter. But look at the very strong category — it’s kind of around the average.
This is where we have to dive in a little bit further. Even though a very strong El Niño shows about average snowfall, it’s really varied. The graphic here shows the average snowfall in that white shaded box for ACY Airport and in Long Branch (pretty much the Jersey Shore). We saw back in 2015–16 above-average snowfall, but 1972–73 as well as 1997–98 saw next to nothing.
So while generally I do believe that a very strong El Niño trends toward a less snowy than average winter, there are exceptions to this — and in some cases, pretty significant snowy exceptions like we saw in 2015–16.
Short-Term Outlook
In the short term, there’s not much to worry about. We’re going to have a less active than usual hurricane season — that’s good news. It doesn’t really have too much of an impact on our summer temperatures or precipitation.
However, as we go into the winter, we’re going to have to pay close attention to what strength of El Niño we end up with.Quick Recap:
A very strong El Niño means a much milder than average winter, but has mixed results as to how snowy our winter could be here in New Jersey.
A strong El Niño means a slightly milder than average winter and well below average snowfall.
- A strong El Niño means a slightly milder than average winter and well below average snowfall.
- A very strong El Niño means a much milder than average winter, but has mixed results as to how snowy our winter could be here in New Jersey.
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