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 the hail to the radar, and the echo is further away from the radar than the actual location of the hail on the same radial path, forming a cone of weaker reflectivities. More recently, the polarization properties of weather radar returns have been analyzed to differentiate between hail and heavy rain. The use of differential reflectivity (formula_1), in combination with horizontal reflectivity (formula_2) has led to a variety of hail classification algorithms. Visible satellite imagery is beginning to be used to detect hail, but false alarm rates remain high using this method. The size of hailstones is best determined by