A "tumbleweed tornado" outside of the ABQ City Limits. Taken by Hassan Ahmad on March 31, 2016. A popular 1990s country song by Sylvia Robinson goes, "Tumbleweed, you're living a cowboy's dream. Tumbleweed, freedom is in the air you breathe." Anyone who is familiar with the climate of New Mexico knows that the windiest time of year is generally during the spring months of April and May (with March and June often times not far behind). By March or April, the polar jet stream has started migrating northward, but can often influence the southwestern U.S. with wind speeds varying with height. Meanwhile, the sun angle is getting higher in the sky and creating greater heating near the surface of the earth. The heated surface air rises to a greater depth of the atmosphere during these spring months, often to a height between 7,500 and 10,000 feet above the surface. The rising air mixes with stronger winds aloft, resulting in stronger and turbulent winds mixing down to the surface. Strong surface pressure gradients can enhance surface winds. High wind events across New Mexico can also occur with strong surface fronts, especially those that race through the eastern plains.
One example of such a system occurred in late March 2016, where chances were good that the wrath of the state’s spring winds were felt. As a potent upper low emerged east of the Sierra Nevadas overnight Monday into Tuesday the 29th, isolated rain and snow showers hugged the NM/CO state line. Windy to very windy conditions were also forecast, with the strongest gusts of 60-65 mph across the southwest and south-central mountains. Unseasonably warm conditions persisted with widespread critical fire weather conditions across the eastern plains. However, temperatures were going to begin their drop Tuesday afternoon across western New Mexico behind a cold front that was to shift from west to east Tuesday night. Conditions continued to remain quite windy across the eastern plains on Wednesday. By Thursday, March 31st, a cold front was to approach northeastern NM backing southward Thursday night, while a second low developing across southern Arizona sagged southward. In Albuquerque, the Sandia Mountains to the east disappeared behind clouds of dust, pollen, and tumbleweeds, as city officials alerted people to stay inside and avoid breathing the dust. Then, several videos and pictures began to emerge- if there was ever a moment to fully capture what spring is like in New Mexico, it would be… a tumbleweed tornado! Now, this “tumbleweed tornado” would technically be a dust devil. According to the American Meteorological Society (or AMS), a dust devil is defined as a “small, but vigorous whirlwind, usually of short duration, rendered visible by dust, sand, and debris picked up form the ground”. A tornado, on the other hand, is defined as “a violently rotating column of air in contact with the surface and extending from a cumulonimbus (thunderstorm) cloud often visible as and/or circulating debris/ dust at the ground”. Dust devils form when hot air near the surface rises quickly through a small pocket of cooler, low-pressure air above it. If conditions are just right, the air will begin to rotate. Dust can occur with thunderstorm wind gusts or strong non-thunderstorm winds, reducing visibilities to near zero at times. While high wind events are relatively common across New Mexico, these strong winds can cause significant impacts to life and property. Strong winds can damage buildings and uproot trees, but can also produce areas of blowing dust that can reduce visibilities making road travel hazardous. If caught in a dust storm on the road, remember to always pull completely off the road and take your foot off the brake if stopping due to low visibilities. To learn more about other drought topics across the desert southwest, please click here! ©2020 Meteorologist Sharon Sullivan
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