https://www.youtube.com/watch?v=8h7k2cNruDc&feature=youtu.be  

Difficulties of Predicting Snow Accumulation Amounts

Winter weather can be one of the most difficult weather events meteorologists have to forecast. It’s not because meteorologists don't understand how winter weather works, but it all comes down to the shape of each snowflake. Most of us have heard the saying “there are no two snowflakes alike". It's a statement that holds some truth. It’s one of the many reasons why meteorologists have such a difficult time predicting snow accumulation amounts. For the most part, there are four different types of snow crystal types. They come in the form of plates, columns, needles, and the typical snowflake shape, called a dendrite. When dendrites start to accumulate, their barbs tend to stick together. This allows air to be trapped between the snowflakes as the snow accumulates. If enough snow falls, it can produce greater snow accumulations because of the trapped air between the ice crystals. Between needles, plates, and columns, they do not stick together as easily because they do not have barbs. This allows the snow crystals to compact closer together, sometimes giving lesser snow accumulation amounts than that of a dendrite-dominant storm. This is one major reason why meteorologists have such a difficult time predicting snow accumulation amounts. Not to mention the development of persistent snow bands, how much water content is available for a winter storm, or what temperature the surface is. These are all factors that make forecasting winter weather so challenging. For WeatherNation - Meteorologist Josh Cozart.