Chicago’s O’Hare International Airport has been hit by a tornado causing hundreds of flights to be disrupted.
According to the National Weather Service (NWS) in Chicago, the tornado arrived around 7pm on Wednesday July 12 and had moved on by 8pm.
At the time of its arrival, the service warned: “This tornado has been touching the ground intermittently so far and is moving east. There are additional circulations along the line south of O’Hare. Seek shelter if in the warned area.”
The NWS issued two warnings on Wednesday evening and tornado sirens were sounded across Chicago to warn people to seek shelter.
Videos from the day showed hundreds of passengers taking shelter in an airport concourse.
A confirmed tornado is on the ground near O'Hare airport! This tornado has been touching the ground intermittently so far and is moving east. There are additional circulations along the line south of O'Hare. Seek shelter if in the warned area! https://t.co/lirNZotdNn
— NWS Chicago (@NWSChicago) July 13, 2023
FlightAware, a flight tracking service, has reported that around 169 flights were cancelled and nearly 500 were delayed as a result. According to local news outlets, warehouses near the O’Hare International Airport have suffered some damage.
Tornados are not uncommon in Chicago. According to the NWS, 97 significant tornados were recorded in the Chicago metro area between 1855 and 2021.
The deadliest one to date was on April 21, 1967, when the tornado formed in Palos Hills in Cook County and travelled 16 miles through the south side of Chicago, taking the lives of 33 people, injuring 500 and causing over $50 million of damage.
Below is a map highlighting areas where we suspect tornadoes may have touched down last evening. Our team will be out surveying damage today to determine exactly where these tornadoes tracked. Stay tuned for updates over the next several days. #ILwx pic.twitter.com/SafDnyI3uF
— NWS Chicago (@NWSChicago) July 13, 2023
How does a tornado occur?
A tornado is a rotating, violent column of air that extends from the ground to a cumulonimbus cloud or sometimes the base of a cumulus cloud.
Also referred to as a twister, cyclone or whirlwind, it comes in many shapes, sizes and speeds.
While most tornadoes have wind speeds that are less than 110mph, a tornado can reach over 300mph.
They mostly occur in North America as it is a large continent that extends from the tropics to the Arctic regions, and has no major east-west mountain ranges to block the airflow between the two regions.
