Winter weather is upon us. This week in weather extra, Ryan and Tom talk about the conditions required for winter precipitation. Ryan - There are plenty of different types of precipitation that can fall from the sky in the winter. Snow, sleet, freezing rain and sometimes rain. They all require very specific conditions in the atmosphere. The atmosphere has different layers...all of which can have different temperatures. Each form of winter precipitation needs a different combination of atmospheric temperatures to form. We’ll use the passage of a cold front to show how precipitation changes. With warm air, air above freezing precipitation stays liquid all the way to the ground. As cold air advances and forces the warm air up, the rain stays liquid, but the ground gets colder. In some cases, objects at the earth's surface are well below freezing, and when the colder raindrops hit those surfaces the rain freezes coating them in ice. We call this freezing rain which is sometimes referred to on a large scale as an ice storm. The warm air continues to advance and some of the raindrops actually start to freeze. Some snowflakes may even be mixed in and some may melt on their way down to the ground. We call this mix of ice rain and snow by one name. Sleet. The cold air continues to move in over a region and the cold layer gets thicker. Now, up in the clouds, the water that previously was used for the raindrops starts to crystalize into six sided flakes. The flakes stay frozen all the way to the ground and snow is the result. Winter precipitation types can sometimes be a challenge to forecast. Each cold air and warm air layer need to be just right to produce each type of frozen and freezing precipitation. If you would like to learn even more about winter precipitation, log on to www.kxnet.com/weatherextra and check out the blog. Ryan will post more detailed information in the weather extra blog. And if you have a question or an idea for...