Climate sceptics, led by President Trump, were quick to jump on the bandwagon when extreme cold weather hit the US at the end of January 2026. Trump posted on his ‘Truth Social’ account: “Rarely seen anything like it before. Could the Environmental Insurrectionists please explain – WHATEVER HAPPENED TO GLOBAL WARMING???”
He was promptly served by climate scientists who patiently explained what was going on with the winter weather.
A massive winter storm moved from New Mexico to New England, dumping ice, sleet, snow and bitter cold across the United States. Hundreds of thousands of people were left without power when ice-laden tree branches broke power lines, while the Midwest and Northeast saw more than a foot of snowfall. The intensity of the low-pressure system was amplified by an unusual convergence of atmospheric conditions high above the Earth’s surface.
Winter low-pressure systems thrive on sharp temperature contrasts near the ground and a southward deflection in the jet stream, which steers weather systems. In this case, deep Arctic air masses collided with warm, moist air from the Gulf of Mexico, providing the fuel for heavy precipitation. Crucially, the polar vortex – a fast-moving band of air circling about 20 miles above the North Pole – extended far southward, overlapping the jet stream above the US. This configuration allowed upward atmospheric waves to bounce back and forth between the vortex and the mtroposphere, amplifying the north-south movements of the jet stream and intensifying the cold and snowfall at the Earth’s surface.
Even as the Earth warms, severe winter periods can still occur. Climate change weakens and destabilises the stratospheric vortex, making such southward excursions more likely, while a warmer ocean provides additional moisture that can amplify extreme precipitation. Research indicates that while cold spells may become less frequent, the most extreme winter storms may become stronger, and more precipitation may fall as wet snow or freezing rain rather than snow.
Scientists continue to refine models and observations — work that depends on continued federal support — to improve predictions and understand these complex interactions. Unfortunately, the Trump administration is doing everything it can to dismantle that scientific work.
The website Skeptical Science gives a full explanation of the occurrence of severe winter storms in a warming climate.