This week’s Arctic blast across Lower 48 pales in comparison to cold snaps of the past

Temperatures plummeted across the Lower 48 this week, prompting wind chill advisories and warnings in 30 states. Wind chills reached minus-60 to minus-70 in Montana and North Dakota, with temperatures some 30 to 50 degrees below average in the nation’s heartland.

At one point, Mississippi was as cold as the North Pole. Nearly 4 feet of snow fell just south of Buffalo. And calendar-day low temperature records were smashed across the southern United States.

But despite the bitter cold, few monthly or all-time cold records were set. Simply stated, even a severe and disruptive Arctic outbreak isn’t netting the kinds of records or headlines that those of the past did.

The reason for this is simple: The Earth is heating up. Warm extremes are turning warmer, and the cold generally isn’t as cold. Human-caused climate warming is moderating cold snaps, making them less severe. They can still be bitter and dangerous, but they’re not quite as bad as they used to be.

This week’s Arctic blast in context

The Arctic blast across the Lower 48 states over the past week has no doubt been intense and helped record cold outpace record warmth. Since Jan. 1, there have been 332 cold temperature records compared to 211 warm temperature records.

If cold is trumping warmth so far this year, how can one claim that human-caused climate warming is still at work? First, consider that these numbers only apply to the past 16 days. Scientists look at trends over much longer periods to detect a climate signal.

In 2023, 31,611 warm-weather records were set compared to just 10,493 cold-weather records.

Furthermore, the 332 cold-temperature records set since Jan. 1 are calendar-day or daily records, which are relatively easy to beat. Monthly records, representing the most extreme temperatures over a period 28 to 31 times as long, are much tougher to break. All-time records, encompassing all 12 months, are the most difficult to achieve.

Only two monthly cold records have been set since Jan. 1. And just as many record highs occurred in that same period.

If we examine monthly temperature records set over longer periods than just the first 16 days of January, the disproportionate number of record highs becomes starker:

- Over the past 30 days, there have been 52 monthly warm records compared to just two monthly cold records.

- Over the past 12 months, 3,302 monthly warm records have occurred compared to 1,006 monthly cold records.

And since this cold snap began, only one all-time record low has been set. Although no all-time record highs have been set this month, over the last year there have been 473 of them compared to just 14 all-time record lows.

The disproportionate number of warm-weather records reflects simple math. Weather is filled with dips and spikes; we call that “natural variability.” But if those dips and spikes are superimposed on a background of warming air, suddenly the dips don’t dive as low, and the spikes surge higher.

What does that look like? An example: In December 2019, parts of Alaska dipped to minus-50, but the state still nabbed what then was its hottest year on record.

A few cold snaps don’t negate a disproportionate number of warm events, particularly when the cold isn’t as cold and the heat is that much more extreme.

Could climate change worsen cold snaps in some areas?

There has been some literature to suggest that, even as the world heats up, a more disrupted polar vortex and chaotic jet stream could allow lobes of cold to descend to the mid-latitudes with increasing frequency. But the evidence is unclear as to the degree this is actually happening.

In the meantime, as the cold continues to fester over the central and eastern states, it won’t last long. According to the National Weather Service’s Climate Prediction Center, odds favor a return to well-above-average temperatures by next week.

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Jason Samenow and Ian Livingston contributed to this report.