Outflow boundary a downburst. "Gustnadoes", short-lived vertical circulations near ground level, can be spawned by outflow boundaries. Gust fronts create low-level wind shear which can be hazardous to planes when they takeoff or land. Flying insects are swept along by the prevailing winds. As such, fine line patterns within weather radar imagery, associated with converging winds, are dominated by insect returns. At the surface, clouds of dust can be raised by outflow boundaries. If squall lines form over arid regions, a duststorm known as a haboob can result from the high winds picking up dust in their wake from the desert floor.
Desert are found in Central Asia. Others occur on the eastern side of the Rocky Mountains, the eastern side of the southern Andes and in southern Australia. Polar deserts are a particular class of cold desert. The air is very cold and carries little moisture so little precipitation occurs and what does fall, usually snow, is carried along in the often strong wind and may form blizzards, drifts and dunes similar to those caused by dust and sand in other desert regions. In Antarctica, for example, the annual precipitation is about on the central plateau and some ten times that amount