Before Hurricane Milton made landfall this week, supercell thunderstorms—which have revolving updrafts and have the potential to spawn tornadoes—raced across the state, bringing with them an earlier-than-expected dose of pandemonium.
The National Weather Service issued 126 tornado warnings as a result of the ensuing twisters, and 45 preliminary tornado reports were received by the center’s Storm Prediction Center.
Five fatalities from a tornado that ripped through a retirement complex in St. Lucie County account for over one-third of the 17 hurricane-related deaths that have been confirmed thus far.
Although Florida is used to tropical storms but less so to strong twisters, the state is now experiencing its worst number of fatalities and property damage from the tornado outbreak as it starts the protracted process of cleaning up and recuperating from Hurricane Milton.
One of the strongest tornadoes ever recorded in South Florida history occurred on that day, which is likely to go down in Florida history as one of the worst tornado outbreaks ever recorded there during a storm.
According to a preliminary assessment from the National Weather Service, the whirling winds in Palm Beach Gardens reached speeds of 140 mph, knocking off significant pieces of roof on freshly built residences and pulling apart concrete walls.
Donal Harrigan, a Miami-based NWS meteorologist, stated, “That’s the first EF-3 for our South Florida area, from Lake Okeechobee and southward, on record.” A tornado classified as an EF-3 with estimated speeds of 136 to 160 mph (EF stands for the Enhanced Fujita Scale, which the National Weather Service began using in 2007).
After damage assessments, a number of additional observed twisters could be rated as EF-3s, according to Harrigan.
“Historically, you could probably count on one hand the number of EF-3s that have existed in the state. We could have more than one of those in a single day,” he stated.
Overall, this year has witnessed an exceptionally high number of powerful tornadoes connected to storms in the United States.
Less than 1% of tornadoes connected with landfalling tropical storms have been classified EF-3 or greater. Tornadoes are prevalent when hurricanes make landfall, but most are on the lesser end of the range. In contrast, EF-3-intensity tornadoes were spawned by four of the five storms that made landfall in the United States this year.
Only five tornadoes caused by tropical storms received that rating between 1995 and 2023.
According to preliminary study, as the planet warms, tropical storms may create more tornadoes. Researchers simulated storms Ivan, Katrina, Rita, and Harvey in a warmer future climate for a study that was published in June. Their findings suggested that, if the rate of pollution from fossil fuels doesn’t change, the frequency of tropical cyclones that might create catastrophic storms could rise by 56% to 299% by the middle of the century.
Whether climate change contributed to the storm-related twisters this year is yet unknown. However, Bill Gallus, an Iowa State University meteorology professor and one of the study’s authors from June, claimed that “it was really unusual how unstable conditions were in South Florida” during Milton.
When temperature and density variations let air pockets to rise and fall quickly, these are the kinds of unstable circumstances that give birth to thunderstorms.
When I viewed the instability chart, I was taken aback. According to Gallus, it was as high as one could see in Kansas during a storm pursuit. “Tornadoes have been produced by hurricanes before, but not this many in just Florida.”
He went on to say that this kind of instability is “what we expect will become more common” in a warming planet.
The fact that the thunderstorms in the hurricane traveled far from its core is one reason Milton saw so many tornadoes.
Gallus observed, “That specific band of showers and storms from Milton seemed to really eject pretty far out in front of the hurricane with the initial tornadoes.”
The thunderstorms that gave rise to tornadoes were those in the outer storm band, which became alone and unaffected by other systems. Experts said it serves as a warning that storms may still pose a hazard even far from their core and well before they make landfall.
Heat is the second essential component of Milton’s tornadoes. The thunderstorms experienced very warm weather as well as wind shear, or variations in the direction and speed of winds at altitude, as the hurricane made its way toward the Florida shore in the afternoon. This made them more potent than they would have been in a more conventional storm configuration.
According to Gallus, “the atmosphere had plenty of time to warm up.” “Most hurricanes result in very little heat from the sun; instead, tornadoes occur in the center of intense downpour.”
Tornadoes often originate on a hurricane’s right side, sometimes referred to as the “dirty side,” and on the front end of the storm in a counterclockwise rotating hurricane like Milton. The strongest winds also frequently hit this region.
Gallus stated that this is how it transpired during Milton: the twisters “occurred right where we see most tornadoes happen.”
However, he pointed out that the tornadoes in Milton’s instance were very close together.
Gallus stated that “the real estate where it was producing tornadoes was small— I would guess it’s the most concentrated outbreak of tornadoes produced by a hurricane” because to Milton’s brief journey over the Florida peninsula.
The precise ways in which climate change may affect the tornadoes that are produced by storms require further investigation. The impact of intense rain on global warming, however, is more pronounced and obvious.
The World Weather Attribution project, a group of scientists that studies extreme weather and is regarded as an authority in determining how climate change affects specific events, released a report on Friday that found that rainfall in one-day events like Milton is now 20% to 30% more intense due to climate change. According to the research, Milton’s wind speeds were probably 10% higher due to the effects of climate change.
The team also discovered that Hurricane Helene had increased wind and moisture due to climate change. According to a second early assessment, in some of the hardest-hit areas, climate change most certainly increased Helene’s rainfall by as much as 50% over the course of three days.
