70% chance it's the strongest El Niño since 1950: 2 things it does to a US winter — the north won't like either

NOAA has upgraded this thing from "one of the big ones" to "possibly the biggest one ever," and it has opinions about your snow day.

Every few years the Pacific Ocean gets hot, flustered, and decides to rearrange the weather for the entire planet, and every few years we act surprised. This time, though, the ocean is not doing its usual mid-tier El Niño. It's going for the record.

According to CNN's meteorologists, the El Niño currently building in the tropical Pacific is strengthening fast, is forecast to hit "Super" status no later than October, and has a nearly 70 percent chance of becoming the strongest El Niño on record by the end of the year. NOAA's records go back to 1950, so "on record" means "since your grandmother was in saddle shoes."

Nat Johnson, a meteorologist at NOAA's Geophysical Fluid Dynamics Laboratory, told CNN this is "very unusual, if not a once in a lifetime" kind of strength. Scientists do not say "once in a lifetime" casually. They say it when they've triple-checked the models and would like everyone to put down their coffee.

Quick refresher for those who slept through earth science

El Niño is a natural climate cycle. Water along the equator in the Pacific gets warmer than average, the atmosphere above it reacts, and that reaction ripples outward like someone cannonballing into a kiddie pool. The stronger the El Niño, the more reliably those ripples show up where forecasters expect them.

One caveat CNN and NOAA both insist on, so here it is: a historically strong El Niño does not guarantee historically dramatic weather. It tilts the odds. It does not write the script. Got it? Great. Now here are the two things it tends to do to an American winter.

Thing one: the jet stream moves to Florida like everyone else

In a typical El Niño winter, the jet stream — the cross-country river of air that storms ride — drops south of its usual track and parks over the southern tier of the US. NOAA's explainer lays out the consequences:

• The South gets more storms, more rain, and cooler weather.
• The North turns warmer and drier.
• The Southeast and southern Plains can get the cold-plus-wet combo that produces snow, sleet, and freezing rain, depending on how cold it actually gets.
• Florida sees a higher risk of winter severe thunderstorms, per Columbia climate scientist Michael Tippett, while other parts of the Gulf Coast quiet down.

The jet stream is essentially relocating to the Sun Belt for the season, and it's taking the storms with it. Northern states get the warm, dry leftovers.

Thing two: the north's snow budget gets cut

This is the one that's going to hurt in Buffalo. Warm plus dry is not a recipe for snow, and NOAA's data via Climate.gov shows that strong El Niño winters bring less snow on average to the Northeast. Add the fact that the Climate Prediction Center's December-through-February outlook already has its highest odds of above-average temperatures stretched across the entire northern tier, from the Pacific Northwest to the Midwest, and the math does itself.

A few more things from the early outlook worth filing away:

• Warmer-than-normal temperatures are on the table for more than half of the Lower 48.
• Wetter-than-normal conditions are possible for Southern California, the whole southern tier, and even the East Coast, with the highest confidence in the Southeast.
• The drier-than-normal zones are confined to the north, where it's also expected to be warmer. Again: hot and dry do not make snowmen.

The part where it's not just El Niño

El Niño gets the headlines, but it's working with a partner. According to Climate Central, winter is the fastest-warming season for most of the US, and their snowfall analysis found annual snow totals have dropped in nearly two-thirds of the country since 1970. So the northern tier was already on a snow diet. El Niño is just the trainer showing up to confiscate the cookies.

A record El Niño layered on top of the fastest-warming season in the country is less a weather event than a group project where one member is doing all the work and the other is a warming planet.

In conclusion

If you're in Atlanta or Dallas, buy an umbrella and maybe a real coat. If you're in Minneapolis, your skis may spend the winter as a decorative wall feature. If you're in Florida, you already knew, on some level, that you'd be the exception to everything.

And if you are a northerner who loves snow: I'm sorry. The ocean did this, not me.