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So it could have been a tornado. Maybe just barely in the making and never touched down. Cool!
...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 may begin to rotate. As the air rises suddenly, the column of hot air is stretched vertically causing intensification of the spinning effect by the scientific principle conservation of angular momentum. The secondary flow in the dust devil causes other hot air to speed horizontally inward to the bottom of the newly-forming vortex. As more hot air rushes in toward the developing vortex to replace the air that is rising, the spinning effect becomes further intensified and self-sustaining. A dust devil, fully formed, is a funnel-like chimney through which hot air moves, both upwards and in a circle. As the hot air rises it cools, loses its buoyancy and eventually ceases to rise. As it rises it displaces air which descends outside the core of the vortex. This cool air returning acts as a balance against the spinning hot air outer wall and keeps the system stable.The spinning effect, along with surface friction, usually will produce a forward momentum. The dust devil is able to sustain itself longer by moving over nearby sources of hot surface air.As available extreme hot air near the surface is channeled up the dust devil, eventually surrounding cooler air will be sucked in. Once this occurs, the effect is dramatic and the dust devil dissipates in seconds. Usually this occurs when a dust devil isn't moving fast enough (depletion) or begins to enter a terrain where the surface temperatures are cooler, causing unbalance.Certain conditions increase the likelihood of dust devil formation. * Flat barren terrain, desert or asphalt: Flat conditions increase the likelihood of the hot air "fuel" being a near constant. Dusty or sandy conditions will cause particles to become caught up in the vortex, making the dust devil easily visible. * Clear skies or lightly cloudy conditions. The surface needs to absorb significant amounts of solar energy from the Sun to heat the air near the surface and create ideal dust devil conditions. * Light or no wind and cool atmospheric temperature. The underlying factor for sustainability of a dust devil is the extreme difference in temperature between the near surface air and atmosphere. Windy conditions will destabilize the spinning effect of a dust devil....
It again looked like a rocket had taken off, but the bottom part of the smoke trail was missing today.Next time I catch it I will pull over no matter where and snap a picture.