CHICOPEE, Mass. (WWLP) – Some areas received wintry weather Wednesday morning in western Massachusetts with snow, while others got freezing rain.
22News Storm Team Meteorologist Kelly Reardon explains how different types of precipitation form. First, it’s important to note that all precipitation starts high in the sky where the temperature is well above freezing, so it all technically starts as snow.
With rain, there is a thick layer of warm air from the surface and upward, so the precipitation falls as rain. With freezing rain, it starts as snow, then encounters a layer of warmer air where it melts into rain. But, there is a shallow layer of sub-freezing air near the surface, like the ground or your car. So the rain freezes upon contact with those surfaces.
Sleet starts as snow, melts in a warmer layer, but then encounters a much thicker layer of below-freezing air before touching ground, allowing it to partially refreeze. That’s why sleet is so wet. With snow, the entire column of air is below freezing.