(Map via WeatherBell)
A white Christmas is defined as 1 inch of snow on the ground at 7 a.m. Christmas morning. The last white Christmas in Des Moines was two years ago. This year will not be a white Christmas, and it won’t be across much of the United States.
Chances for a white Christmas – by 30-year average
Between 1993 and 2023, there were 14 “white Christmases” — the exact same number observed in the previous 30-year period from 1963 to 1993.
What does this tell us? It means the likelihood of experiencing a white Christmas is around 46%, a rate that has remained remarkably consistent over the past six decades.
Snowfall in a warming world: It’s not as simple as ‘less snow with climate change’
When people think about climate change, the image of melting ice caps and warmer winters often comes to mind. However, the reality of how climate change impacts snowfall is far more complex. In fact, in some areas, snowfall may increase or remain stable despite rising global temperatures. Here’s why.
A basic principle of meteorology is that warmer air can hold more moisture. For every degree Celsius of warming, the atmosphere can hold about 7% more water vapor. When temperatures hover near freezing, this increased moisture can fuel more intense snowstorms.
This is especially true for regions that typically experience temperatures just below freezing during winter. As a result, instead of suppressing snowfall, a warming climate can supercharge it — at least temporarily.
For example, regions like the Northeastern United States have seen several historic blizzards in recent decades. The 2015 “Snowmageddon” in Boston and the record-setting snowfall events in Buffalo, New York, illustrate how warmer oceans and more atmospheric moisture can lead to extreme snowfall events.
December warming
December temperatures are steadily rising, a trend that signals broader climate shifts. In Des Moines, for instance, the average December temperature has increased by 2.1°F since 1878. As we spend more time above 32ׄ°, the chances for a white Christmas will begin to drop – despite this short-term increase in snowfall.
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