February 16, 2015 — It’s estimated that lightning strikes the United States over 20 million times each year. Given this amount of lightning activity, shouldn’t we expect to see a little lightning and thunder in the dead of winter? Interestingly enough, weather reports across the country have tallied quite a few incidents of “thundersnow” (a rare weather phenomenon that brings the unusual combination of thunder, lightning and snow) this winter. While hype about the phenomenon seems to be on the rise, according to the National Weather Service (NWS), thundersnow is so rare that it only occurs in less than one percent of observed snowstorms.
“Clouds are low in the winter so you don’t get that upward vertical motion that you get with your warm sector of thunder storms in the summer. It’s rare to have thunder and lightning in the winter. It usually means it’s a strong intense winter storm or a blizzard,” explained Kate Mantych, WDTV 5 News Meteorologist.
So what causes this weather phenomenon? The NWS explains that thundersnow occurs when lightning forms after an electric charge separation process in updrafts and downdrafts created inside a convective system. Enhanced air instability, a quick temperature change from surface to cloud, or a charge separation process can all trigger lightning and the ensuing thundersnow.
Since thundersnow is similar to a typical thunderstorm, it’s important to enlist the same safety precautions for spring and summer weather events. Staying indoors and away from trees still applies during thundersnow. Lightning occurring during thundersnow has been known to zap trees, homes, buildings and traffic lights and wide-spread power outages are not uncommon in these storms. Restoration and repair of power lines in severe winter weather can be especially tricky when heavy snows impact travel and road accessibility. Thunderstorm conditions during winter storms can be harder to predict, as well. And while the average bolt of lightning can carry 100 million volts of electrical power, it’s virtually impossible to predict when and where lightning will hit and what its target will be. Lightning can strike miles ahead of a parent thunderstorm and linger several minutes after a storm leaves a specific area—which is why the NWS dubs lightning as “the first thunderstorm hazard to arrive and the last to leave.”
So just what is all of this lightning doing to our homes and buildings? Well, here are a few scary statistics.
Each year, lightning fires are responsible for an estimated:
$450 million in home property damage
$108 million in non-residential property damage
$28 million in damages to storage facilities
$22 million in damages to places of assembly (churches and houses of worship)
$19 million in damages to hotels and motels
$15 million in mercantile and business properties (offices, shops and department stores)
$15 million in industrial and manufacturing facilities
$3 million in miscellaneous properties
(Source: National Fire Protection Association NFPA)
Lightning is an unpredictable weather threat, but mitigation doesn’t have to be hit or miss. The highly conductive materials used in a lightning protection system provide a low resistance path and grounding network to safely dissipate lightning’s dangerous electricity. When a lightning protection network is installed in accordance with national safety standards, lightning’s harmful electricity is intercepted and directed to ground without impact to the structure, occupants or contents. So whether the threat strikes in spring, summer, fall or even winter, lightning protection systems can safeguard vulnerable structures against nature’s underrated fire risk. Think of lightning protection as an insurance policy that provides an ounce of prevention against weather gone wild.
