February 2007 North American blizzard Due to the three-dimensional nature of the atmosphere, warm air was poised to overtake the cold air closer to the ground, causing precipitation to melt, then refreeze as either sleet or freezing rain. As temperatures hovered around freezing on the southern edge of the storm track, light snow accompanied freezing rain and sleet. The freezing rain coated all surfaces with thick layers of ice, including power lines and tree limbs which break under the additional weight. Some locations in the Mid-Atlantic received several inches of sleet. Four inches (100 mm) of sleet caused travel difficulties and hampered cleanup efforts in
Hail with air, wind, and interaction with rain and other hailstones can slow their descent through Earth's atmosphere. Severe weather warnings are issued for hail when the stones reach a damaging size, as it can cause serious damage to human-made structures and, most commonly, farmers' crops. Any thunderstorm which produces hail that reaches the ground is known as a hailstorm. Hail has a diameter of or more. Hailstones can grow to and weigh more than . Unlike ice pellets, hailstones are layered and can be irregular and clumped together. Hail is composed of transparent ice or alternating layers of transparent and