Here’s what you need to know about thundersnow: Winter snowstorm: A fierce winter storm is pummeling the Mid-Atlantic, with Washington, D.C., potentially facing a foot of snow. Thundersnow has been witnessed in St. Louis during this winter snowstorm, characterized by the unusual occurrence of thunder and lightning within a snowstorm. The National Weather Service recently reported thundersnow in the St. Louis, Missouri region amid the harsh winter conditions.
If you’re hearing thunder or seeing flashes of lightning, it’s not your imagination. The current weather conditions involve heavy snow and sleet, with southeastern sections of Missouri experiencing stressed tree limbs breaking and resulting power outages. Heavy snow and sleet are persisting, with the storm expected to continue through the evening. The National Weather Service in St. Louis shared updates via Twitter, informing residents to brace for the storm’s impact.
The uniqueness of thundersnow was highlighted by a local television station, KSDK, which noted that the thunder accompanying the snowfall sounded more muted compared to typical thunderclaps. Due to the mix of sleet, residents described hearing “booms of thunder mixed with the sound of tiny taps.”
So, what exactly is thundersnow? Meteorologists use the term “thundersnow” when thunder and lightning occur during a snowstorm. This phenomenon is typically associated with relatively strong instability and abundant moisture above the surface, often found above a warm front. Thundersnow is commonly observed downstream of bodies of water like the Great Salt Lake and the Great Lakes during lake-effect snowstorms.
Thundersnow is most likely to occur during heavy snowfall, which can obscure visibility for ground observers. While the snow may muffle the thunder, lightning is often visible amidst the snowfall.
The rarity of thundersnow can be attributed to the usual absence of convective activity, the upward movement of air that fuels thunderstorms, in winter months compared to the warmer, summer season when thunderstorms are more prevalent, as noted by the National Oceanic and Atmospheric Administration (NOAA).
Despite its rarity, thundersnow is not entirely unheard of. Lightning with thundersnow can pose risks similar to those in a regular thunderstorm, as lightning can accompany thunder in such conditions. Lightning safety precautions should be taken seriously, regardless of the season, as emphasized by Jack Williams, the founding editor of USA TODAY’s weather page, who highlighted the potential danger of winter lightning strikes.
While winter lightning strikes may be less common, incidents have occurred in the past, such as in 1996 when two individuals were struck by lightning during snowstorms in Minnesota and Colorado. In 2002, four teenagers in Maine were also struck by lightning while sledding, according to the National Lightning Safety Institute.
Thundersnow remains a fascinating and relatively rare weather phenomenon that underscores the unpredictability and diversity of winter weather patterns. The risk of lightning strikes during thundersnow events serves as a reminder of the need for
