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It's an age-old question that occurs to almost everyone this time of year. The above map shows the climatological probabilities of a white Christmas. The new CD Atlas contains 2023 color maps of climatic elements such as temperature,precipitation, snow, wind, pressure, etc.,
chosen to portray the climate of the US. The period of record of the data for most of the maps is 1961-1990. See NCDC's on-line sample maps and information about ordering this product. The map above from the Climate Atlas shows the statistical probability (in percent) that a snow depth of at least 1 inch will be observed on December 25th. Highest probabilities are in northern and mountainous areas of the country. The probability was computed using snow depth observations for December 25th for the full period of record for a given station (rather than just the 1961-1990 climatological normals period).
NCDC also has a separate report which contains maps and tables showing the percent probabilities for a snow depth of at least 1 inch on Christmas morning, as well as the probabilities for a depth of at least 5 inches and 10 inches. The "First Order" (U.S. major airport stations) Summary of Day Dataset for the period of 1961-1990 was used to compute these statistics. Only stations with at least 25 years of data were used and the '61-'90 period was chosen to coincide with the standard period for computing climatological normals. The complete report is available at Will We Have A White Christmas ?
The actual conditions this year may vary widely from these probabilities. The snow on the ground or snowfall on Christmas day will be based on the actual weather pattern during that time. These probabilities are useful as a guide only to show where snow on the ground is more likely. NCDC also has several additional climatological products that can be used to give some clues on where snow is likely. The center produced National Weather Service Snow Normals 1971-2000 - CLIM20-02 for over 500 major U.S. locations. They are available without charge.
NCDC also produced another set of 17 climatic tables called the Comparative Climatic Data. The online version is available without charge and contains monthly mean data for over 250 US cities. Temperature, degree days, and precipitation normals, means and extremes along with wind, humidity, sunshine and cloudiness tables are provided.
Finally, if you would like to keep track of the snowfall across North America on a daily basis, see the NOAA Operational Daily Snow Analysis Charts.
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