March snow is possible in Tennessee, though it is considered transitional. March marks the end of winter and the beginning of spring, meaning the likelihood of wintry precipitation is rapidly decreasing. While not an everyday occurrence, March snow is historically documented across the state, confirming that winter can occasionally linger into the third month of the year.
Historical Probability of March Snowfall
March snowfall averages are lower than the mid-winter months of January and February. Nashville averages approximately 0.7 inches of snow in March, significantly less than the 1.4 to 2.5 inches recorded in January, the state’s snowiest month. Knoxville also sees a diminished average of just under one inch for the month, based on records dating back to 1884.
The chance of a major event is low, but not zero. In the Knoxville area, only 25 snowfalls of two or more inches have been recorded in March over a 132-year period. Historically, significant winter events have occurred in March, such as the 17-inch record snowfall in Nashville in 1892, which remains the city’s largest single-day accumulation. Across the state, March averages only one or two days with measurable snow, highlighting its infrequency compared to earlier in the year.
Geographic Differences in Snow Likelihood
The probability of March snow varies across the state due to Tennessee’s varied topography. East Tennessee, home to the Appalachian Mountains and the Cumberland Plateau, has the highest likelihood of late-season snow. Higher elevations in this region, such as Mount LeConte, receive significantly more annual snowfall because cooler air is trapped and orographic lift enhances precipitation.
The Cumberland Plateau and areas like Crossville see greater March averages, sometimes exceeding two inches for the month, while valleys below, such as Knoxville, see less. Middle Tennessee, encompassing the Nashville area, experiences a moderate chance of snow, with light dustings being the most common outcome. West Tennessee, including Memphis, has the lowest probability, often seeing only traces of snow or a mix of winter rain.
Typical Accumulation and Duration of March Events
March snow events result in minimal accumulation across lower elevations, often less than one inch, but the snow is usually wet and heavy. These late-season snowfalls occur when surface temperatures are marginal, leading to a higher liquid-to-snow ratio that creates dense, sticky snow. The impact of such events is short-lived due to the sun’s increased angle and warming ground temperatures.
Snow that falls melts quickly, sometimes disappearing by late morning or early afternoon. This rapid melting occurs because the ground has begun to warm after the winter months, and the average daytime high temperature in March is rising, often reaching the mid-60s by the end of the month. While major storms have occurred, the common March snow is a brief flurry that does not persist for more than a day or two in most areas.
Meteorological Conditions Required for Late-Season Snow
March snow requires an atmospheric setup involving the clash of two air masses. The primary factor is the lingering intrusion of a cold air mass, originating from the Arctic or Canada, pushing south into the region. This late-season cold air must meet significant moisture, which becomes increasingly available as the Gulf of Mexico contributes warmer, more humid air into the South.
The transition from winter to spring creates a volatile environment where strong low-pressure systems track across the Tennessee Valley. These storms pull Gulf moisture northward, interacting with the cold air mass already in place, leading to precipitation that falls as snow rather than rain. The swift movement of these systems, sometimes called “clipper systems,” can cause rapid temperature drops, forcing the changeover from rain to snow even when surface temperatures are marginally below freezing.