Although these are common source regions, if conditions are right, then a mid-latitude cyclone winter storm can develop pretty much anywhere in the mid-latitude and polar region. There are several common source regions that mid-latitude cyclone winter storms can have for their initial development. Upper level lows are notorious for their explosive development or rapid decay. The intensity of an upper level low can be misleading from the models. Model vertical resolution is poorer in the upper levels as compared to the surface. Upper level lows can bring unexpected heavy snow. Often the upper level low will be displaced hundred(s) of kilometers to the west or northwest of the surface low. Watch mid-latitude cyclones that tilt with height. Snow in association with upper level lows (700 mb and higher), however, tend to be more directly below the low track. This region has the greatest combination of cold air and dynamic lifting. The heaviest snow is often in a narrow band. With a winter mid-latitude cyclone (deep cyclone throughout the troposphere), the heaviest snow is typically 100 to 300 kilometers to the left of the cyclone track. So much is on the line with this forecast and arguable the greatest variety of weather data has to be analyzed when putting this forecast together. A winter weather forecast is a big adrenaline rush for a forecaster. Accumulation is also much more scrutinized than with just rain. When predicting rain, it will be in the liquid form but when predicting winter precipitation it can be snow, wet snow, sleet, freezing rain, just a cold rain, freezing drizzle, a wintry mix, a change from one form of frozen precipitation to another, etc. If the public see winter precipitation in the forecast, it is a guarantee they will remember if it does not happen. A winter weather forecast is not easy to forget by the public because it will drastically alter their plans. This writing will be handy to refer to as an introductory guide when analyzing and forecasting a winter precipitation event, especially when examining North American winter storms. This essay is a general overview of issues and data sources related to forecasting winter precipitation.

Many of these analysis and forecasting tools are available online and will be referenced within this writing. In addition, bust concerns and nowcasting aids will be covered. Each of these will be discussed separately. There are various types of winter weather events that are analyzed and forecasted including mid-latitude cyclones, ice storms, lake-effect snows and sleet storms. This informative forecast writing will focus on the weather forecasting tools and concepts that are used to predict winter weather events.

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