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 spike rain core. Since hail cores are most intense at higher elevations, hail spikes usually appear at the levels aloft that accompany the most intense hail. Because of this, hail spikes are usually not seen at lower elevations. Another restriction to detection is that the signal of the radar beam has to do multiple reflections, each time weakening it, and are therefore usually noticeable only in extremely large hailstone cases. In rare cases more than one hail spike has been documented with a single storm in one volume scan. This indicates that more than one hail core exists in the same