Tornadoes that strike overnight are nearly twice as likely to be deadly as those during the day due to a combination of factors, including lack of storm spotter reports and missing alerts for tornado warned storms.
Tornadoes are a large source of fear for many people, and that fear only increases for tornadoes that strike when you're asleep.
That escalation of fear is warranted, because tornadoes that occur at night are nearly twice as likely to be deadly as those during the day, according to a recent study.
Examining 140 years of tornado records, the study led by Stephen Strader from Villanova University found that the proportion of tornado fatalities that occur at night has increased by 20% from 1880 to 2020.
Since 1880, nearly 34% of all tornado fatalities occurred at night, but that percentage has increased to 38% during the past 30 years.
A previous study released in 2008 found that out of roughly 48,000 tornadoes in the United States from 1950 to 2005, nearly one in every 20 overnight tornadoes were killers, compared to roughly one in every 50 daytime tornadoes.
Nocturnal tornadoes killed 24 people in Tennessee on March 3 of 2020. That includes an EF4 twister near Cookeville, Tennessee, which caused 19 of those deaths.
On Dec. 10, 2021, a tornado that touched down at 8:49 PM CST in Tennessee and remained on the ground until 11:47 PM CST killed a total of 57 people along its 165.7 mile path. The tornado had a maximum intensity of EF4 and its track passed through Tennessee, Kentucky and Ohio.
(MORE: Kentucky Tornado Recovery, Three Months After the Disaster (PHOTOS))
Why Is There A Higher Percentage Of Nighttime Deaths?
Some reasons for this are fairly obvious.
Unless lit by at least somewhat frequent lightning, you may not see a tornado at night.
One challenge the meteorological and social science communities face is getting the public to take shelter immediately, without first "confirming the threat" of a tornado by looking outside, wasting precious seconds to reach shelter.
It is also harder for meteorologists to confirm tornadoes in progress at night because fewer storm chasers and storm spotters are willing to take the risk of going out at night.
For people that may be in the path of a nighttime tornado, many aren't awake.
"Another problem is that people are often asleep and caught unaware," said Dr. Greg Forbes, former severe weather expert at The Weather Channel.
If you're a sound sleeper or don't have a way to receive warnings overnight, the consequences could be deadly.
If you sleep through a tornado warning, you lose valuable time needed to get to a safer location.
Where we are at night is another important factor.
Where Nighttime Tornadoes Are Most Common
At least 30% of all tornadoes touched down at night for 13 states from Oklahoma to West Virginia from 1950 to 2019, according to the study.
The peak state was 46% in Tennessee.
The high frequency of nighttime tornadoes in the Southeast is especially concerning when it comes to safety and preparedness because of the high amount of manufactured and mobile homes in the region, which are very susceptible to damage in severe weather.
In fact, manufactured homes include the highest percentage of tornado fatalities (40%) compared to other locations despite only making up approximately 6% of U.S. housing.
Nighttime Tornadoes: A Year-Round Concern in the South
Unlike other parts of the country enduring harsh winter cold that prevents the instability needed for severe weather, tornadoes can be a concern any time of year in parts of the South.
So, given the fewer hours of daylight, plus the sun setting an hour earlier than summer months due to standard time, any cold-season Southern tornadoes have a greater chance of occurring after sunset.
Even the core winter months of December through February have averaged three to six nocturnal tornadoes in the U.S. each month from 1953 through 2015, according to NOAA's Storm Prediction Center.
There's also a pronounced nighttime tornado maximum in November, coinciding with the often-discussed "second season" for severe weather targeting the Deep South.
These colder-month tornadoes often occur with a very strong jet stream, meaning winds aloft can move the parent supercells or squall lines in which these tornadoes are embedded at speeds of 60 mph or more, giving little time to seek shelter.
Also, the public's overall awareness of severe weather may not be as high during the winter months, even in areas that can and do experience severe weather any month of the year.
What You Can Do To Stay Prepared
How can you be warned if you're sound asleep? Here are some tips:
-Buy a NOAA weather radio. You can find these at most electronics retailers. They feature warning alarms that can be set to sound loudly when any National Weather Service tornado or severe thunderstorm watch or warning is issued.
-Your smartphone can alert you. Most newer smartphones are capable of receiving wireless emergency alerts from your local NWS office. These include tornado warnings. Make sure your smartphone is charged sufficiently and left on overnight, and a special tone and vibration will occur twice when a tornado warning is issued. Note, however, this will not sound for a tornado watch or severe thunderstorm warning.
-Other weather apps can also alert you. Many weather apps, including The Weather Channel and Weather Underground apps, can send alerts to your smartphone, tablet or smartwatch.
-Know where to go. "Be sure you know your safe location ahead of time so you can get there quickly, even if you have to get there in the middle of the night," said Forbes. "Keep flashlights handy."
In general, your awareness of the threat for overnight severe weather, before you go to sleep, is very important.
If there is a severe thunderstorm or tornado watch extending into the overnight hours or a threat of severe weather developing overnight, make sure your weather radio or smartphone is ready to alert you. It may save your life.