Rare, Widespread Snow in the Atacama Desert

In August 2026, back-to-back winter storms left elements of the Atacama Desert in northern Chile coated in a uncommon blanket of snow. The usually arid area has seen snowfall earlier than, notably in 2025 and earlier than that in 2011. However one of many 2026 occasions was unusually widespread, stretching from the Andes to close the Pacific coast.

The OLI (Operational Land Imager) on the NASA-USGS Landsat 8 and Landsat 9 satellites captured these photographs (above) on August 6 and August 14, earlier than and after a interval of extreme climate, respectively. They present an in depth view of the Chajnantor plateau throughout the Altiplano-Puna volcanic complex, house to the Atacama Large Millimeter/submillimeter Array (ALMA)—one of many planet’s strongest radio telescopes. As snow and excessive winds set in, ALMA suspended operations, transferring its antennas right into a protecting survival mode.

One other storm within the second half of the month blanketed a fair wider space with contemporary snowfall. This picture, captured by the MODIS (Average Decision Imaging Spectroradiometer) on NASA’s Terra satellite tv for pc on August 19, exhibits snow extending westward from the Andes, throughout the desert’s hyper-arid core, and near the Pacific coast south of the Chilean port metropolis of Antofagasta. This coastal space is house to a number of different main astronomical observatories, a few of which additionally suspended operations in the course of the occasion.

A lot of the area’s winter precipitation comes from cutoff lows—low-pressure methods that change into minimize off from the jet stream and may sometimes attain northern Chile. That’s what occurred in 2025, mentioned René Garreaud, an atmospheric scientist on the College of Chile. The late-August 2026 storm additionally got here from a cutoff low, however this one spun off from an unusually massive trough—an elongated space of comparatively low atmospheric strain—that spanned an unlimited stretch of the hemisphere, from the tip of South America up into the subtropics.

The atmospheric disruption, mixed with ample coastal moisture, produced precipitation that spanned an unusually extensive swath of the area—offshore, alongside the coast, throughout the core of the Atacama, and over the Andes. Totals reached a magnitude “not often seen within the in any other case extraordinarily arid area,” Garreaud mentioned.

In some areas it fell as rain, not snow. Taltal, as an illustration, on Chile’s northern coast, gathered practically 40 millimeters (1.6 inches) of rain in three days—about 10 instances its annual imply, Garreaud mentioned. “We see these sorts of occasions only some instances, if any, per decade.”

The plentiful precipitation spurred damaging mudflows and flash flooding in elements of northern Chile. The Nationwide Catastrophe Prevention and Response Service (SENAPRED) reported hundreds have been affected and lots of of houses had main injury.

Garreaud famous that the strengthening El Niño is the backdrop for the anomalously moist winter in north-central Chile. Along with the August storms, a major event in July introduced important impacts to the nation’s Norte Chico area. Throughout El Niño, the subtropical Pacific excessive—which usually retains the area dry—weakens, whereas a blocking excessive tends to kind within the South Pacific close to the tip of the continent. Collectively, these shifts push the Southern Hemisphere storm observe equatorward.

NASA Earth Observatory photographs by Lauren Dauphin, utilizing Landsat knowledge from the U.S. Geological Survey and MODIS knowledge from NASA EOSDIS LANCE and GIBS/Worldview. Story by Kathryn Hansen.