In the Big Bend country of West Texas, a region composed of mountains, ocotillo flats, and grassy rangelands of the northern Chihuahuan Desert, weather is often a wily beast. A storm can rise above the arid plains in surprise puffs, turn wicked green in the blue of a Sunday afternoon, and then suddenly dissipate as if collapsing in the effort. Air currents, moisture, and temperature serve as the storm’s coconspirators, revising its characteristics in seemingly predictable yet uncanny ways. Ice, wind, and fire are its progenies, delivering a glass-shattering torrent of hailstones on a balmy spring day, kicking around a whirlwind of dust and flying debris, or, more devastating, striking up a wildfire with 100 million volts of electricity.
Wild weather here can also be a thing of beauty. Anticipating an oncoming West Texas storm inspires both wonder and trepidation—even within the safe confines of shelter. Unlike routine events in day-to-day life, storms are outside of our control, rendering us mere spectators in a performance of immense power. Yet no matter how severe the action, storms leave calm in their wake, delivering the seasons to our doorstep and perpetuating the remarkable cycle of life in the desert.
Watching the evolution of a storm as it develops above a West Texas desert, where the wide-open country allows an unobstructed view of weather’s temperament, provides an eye-witness account of nature’s constructs and a lesson in atmospherics. No two storms are exactly alike, but once you’re aware of the similar forces at work in all of them, they can be as decipherable as antlers interlaced in a thicket’s branches.
Each spring, just beyond my own backyard in West Texas, when the remains of wild chaff blanket the ground and an expanse of dried stubble hides any new green growth, warming air masses move over the high desert range called the Glass Mountains, gaining heat energy from the bowl-shaped plain below. It’s a standard characteristic of this basin-and-range geography, where broad shallow valleys provide a source of convection, causing warm air to rise and transferring heat from the earth’s surface to the atmosphere. As the warm air rises, moisture in the air condenses and forms a cumulus cloud, resulting in the birth of a potential thunderstorm. Should the warm air continue to rise, creating an updraft, the towering cumulus will expand, providing ideal conditions for lightning. Once precipitation—in the form of rain—begins to fall from the cloud (also causing a downdraft), the thunderstorm is in full force, increasing the likelihood of lightning across a significant degree of the storm’s path.
Lightning strikes are routine in the Big Bend, often wielding enough transformative energy to cause fuel such as dried vegetation to spontaneously combust. In fact, lightning is hardly rare here or anywhere else. It happens with such frequency that several hundred strikes will have occurred somewhere on the planet in the time it takes to read this sentence. When circumstances are just so in the onset of a West Texas storm, you’ll see a lightning strike make ground contact in a burst of flames, followed by a fat puff of smoke, as if a magician has made someone disappear.
Hail is to the thunderstorm as the pearl is to the oyster, the result of hard labor made manifest in a stone both iridescent and unique. As moisture continues to rise in the cumulus cloud column, it reaches extreme heights where it freezes, often collecting around bits of dust or ice crystals, and forms hailstones. As long as the updraft keeps the stones aloft they will continue to grow, moving up and down the cloud tower and acquiring layers of ice that give them irregular shapes. Ultimately, the hailstones’ weight overpowers the updraft and they fall. Collateral damage can range from trees stripped of their spring leaves to busted windows and windshields. Even the West Texas cacti suffer a routine thrashing of hail. I have hiked the desert after hail storms and discovered a wilderness covered in the beaten remains of prickly pear and cholla, as if a truncheon-wielding battalion had just passed through.
At the height of its evolution, a thunderstorm will often collapse as a result of the overwhelming power of its own energy. As precipitation falls, creating a downdraft of cooler air, it drives a wall of gusting winds forward, eliminating the source of surface heat and moisture that would feed the storm’s updraft. Deprived of essentials, the storm will dissipate. The entire cycle, in fact, is often quite brief.
One night, camped alongside a back-country canyon in the Bofecillos Mountains west of Big Bend National Park, I watched a storm unleash a fury of rain and lightning in a matter of minutes, then begin to evaporate just as quickly in the August heat. In this final stage of a storm’s cycle, rain may cease but lightning continues to strike. As lightning filled the receding cloud, a torrent of runoff inundated the canyon, covering the small canyon floor like quicksilver in the flashing light. As it drained away, hundreds of fireflies emerged from the wet sand, their soft yellow glow filling the canyon pathway and spilling over its edges, their pulses syncopating with the bright white of lightning.
“The cruel rainstorm may produce a fine harvest,” the femme fatale Lucrezia Borgia is suggested to have said. Seasonal storms are more often a blessing than a curse and bring much-needed rain to this high desert country, where the selection of native forbs and grasses—the humble drivers of a vast arid ecosystem—depend upon moisture to germinate, grow, and reseed. Storms also inundate the canyons and arroyos along remote mountainsides with a welcomed runoff that churns a mixture of soil, detritus, and coffee-colored water, filling wildlife watering holes and raising groundwater levels so that intermittent seeps and springs may flow.
Flooding also submerges the many low-water crossings and culverts that mark this ragged desert territory, creating a sudden surge across roadways with enough force to carry off a vehicle. In fact, as little as six inches of water can render some vehicles buoyant. As is true elsewhere in the state, drivers should wait until waters recede rather than attempt to drive through flooded zones. Out here, a low-water crossing is hardly ever inundated for long, so a small bit of patience reaps big benefits, especially in saved lives.
Unlike the weeklong deluges experienced in other parts of the country, a West Texas storm is often short-lived, and the results can green up the landscape quickly and drop high temperatures by introducing cool breezes. And they almost always come with the added bonus of rainbows that develop along the receding edge of passing rainfall, particularly when storms arise late in the afternoon and are trailed by a clear sky. A prismatic rainbow glowing against a darkened horizon has always been a good omen. But despite their extensive mythology, rainbows are pure illusion, produced simply by the refraction and reflection of light within droplets of moisture. Not only is their detection directly affected by the position of the observer in relationship to the light source (the sun), the bands of color they exhibit are an artifact of human perception. It seems a rainbow’s pot of gold is nothing more than its own beauty observed, surely a satisfying enough reward for doing nothing more than looking up at the sky.
Unlike much of the rest of the state, in West Texas the vast horizon provides an unimpeded view of sky and ground where weather’s theatrics perform above natural landscapes that have yet to feel the compromise of a human-made world. Weather events here appear timeless, almost as old as the world itself, and never fail to inspire awe in the lucky spectator willing to take the time to watch.