Hurricane Milton surged to Category 4 in less than a day. What is 'rapid intensification'?

(This story was updated to add new information.)

On Saturday, a system in the Gulf of Mexico developed into a tropical storm.

Within 24 hours Milton exploded into a Category 5 hurricane with maximum sustained winds of 160 mph and forecasters say more strengthening is possible, although the storm is predicted to weaken slightly before making landfall Wednesday.

Less than two weeks ago, Hurricane Helene spun up into a Category 4 in just days before barreling up the Gulf coast of Florida on its way to smack into the Big Bend area and rampage hundreds of miles inland.

It's called "rapid intensification" when storms quickly surge from windy to catastrophic monsters and it happened to many of the most destructive storms to ever hit our shores. That sort of development doesn't give Floridians much time to prepare, or to flee.

As global warming heats up the oceans , experts say you can expect more .

What is 'rapid intensification'?

According to the National Hurricane Center , "rapid intensification" is when the maximum sustained winds in a tropical cyclone increase at least 30 knots (34.5 mph) in 24 hours. That's a leap of about two categories on the Saffir-Simpson scale , which measures hurricane strength and potential damage from 1 to 5.

"Rapid intensification occurs when a tropical storm or hurricane encounters an extremely conducive environment," Colorado State University meteorologist Phil Klotzbach said in 2020. "Typically, this environment consists of very warm water, low vertical wind shear and high levels of mid-level moisture."

Out of 104 Category 3 or higher hurricanes from 1990 to 2022, 88% of them underwent rapid intensification according to a 2022 study by Klotzbach. Last year, 13 of the 37 named storms in the Atlantic and Pacific rapidly intensified.

Other conditions also can contribute to rapid intensification, such as light upper atmospheric winds under an area of high pressure, which allows a hurricane to ventilate itself and get stronger, Weather.com said.

Here's a look at some storms where it did.

Hurricane Helene was the 4th deadliest storm to make landfall in continental US since 1950

Helene became a raging behemoth in just days, flooding the west Florida coast and swamping the Big Bend area with an 18-foot wall of water when it made landfall on Sept. 26. The massive storm crawled up through Georgia, South Carolina, Tennessee and North Carolina and wiped out entire cities and towns with horrific, relentless flooding.

At least 231 people were reported dead as of Sunday, October 6, and hundreds more have still not been located. Search and rescue teams continue to hunt through stream beds and debris piles in secluded or hard-to-reach areas of North Carolina's western mountains, navigating around washed-out roads and bridges.

Costs from Helene’s path of destruction across the southeastern U.S. are expected to surpass $30 billion, according to one analysis.

Hurricane Beryl broke lots of records

Last year, Hurricane Beryl changed a lot of record books .

It was the first hurricane on record to reach major hurricane status before July 1 (it hit Cat 3 on June 20), it was the first to do so that quickly before Sept. 1, and it was the earliest-forming Category 5 hurricane on record, among other things.

Beryl grew from a tropical depression with 35 mph winds into a major hurricane with 115 mph winds in under 42 hours. It ultimately made landfall three times , in Grenada, Quintana Roo and Texas, peaking at Category 5 at one point.

Just a few other notable recent storms that got very strong very quickly:

• Hurricane Laura, 2020 : From becoming a tropical depression on Aug. 20 to a tropical storm, Laura became a hurricane in the Gulf of Mexico on Aug. 26 and rapidly spun up into a Category 4 hurricane with peak winds of 150 mph before making landfall in Louisiana . Deaths: 81. Estimated damage: $23.3 billion.
• Hurricane Ida, 2021: Jumped up 65 mph in just 24 hours before it struck Louisiana as a Category 4 hurricane and rampaged across the country. Deaths: 112. Estimated damage: $75.3 billion.
• Hurricane Dorian, 2019: Dorian was the strongest hurricane to ever make landfall in the Bahamas, surging from a tropical storm into one of the most powerful Category 5 hurricanes to make landfall with 185 mph sustained winds. It stalled near Grand Bahama and stayed near that intensity for 24 hours, relentlessly pounding the area. Deaths: 84. Estimated damage: $5.1 billion.
• Hurricane Michael, 2018: Micahel was one of the strongest hurricanes to hit the continental U.S., striking Florida in Bay County as a Category 4 hurricane but not before jumping over 120 mph in three days with a peak at Category 5. Deaths: 74. Estimated damage: $25.5 billion.
• Hurricane Katrina, 2005: Tropical Storm Katrina formed on Aug. 23, 2005 and passed over South Florida as a Category 1 hurricane, weakening back to tropical storm strength. But in the warm waters of the Gulf it rapidly intensified into a Category 5 hurricane and then weakened to a high Category 3 before it devastated southeast Louisiana . Deaths: 1,392. Estimated damage: $125 billion.
• Hurricane Rita, 2005: Rita also hit Category 5 level winds in the Gulf before weakening to a Category 3 and making landfall in Louisiana, flooding communities still reeling from Katrina . Deaths: 120. Estimated damage: $18.5 billion.

Hurricane Patricia was the most powerful fast-growing storm

In 2015, Hurricane Patricia in the Pacific Ocean meandered a bit before becoming a tropical storm, and then extremely favorable conditions fed explosive intensification and it grew into a Category 5 hurricane in just 24 hours.

With maximum sustained winds of 205 mph, Patricia became the most intense tropical cyclone on record in the western hemisphere and the strongest in the world based on wind speed.

Patricia made landfall in Jalisco, Mexico , with wind speeds of 150 mph, the strongest Pacific hurricane on record until Hurricane Otis in 2023.

Contributing: Dinah Voyles Pulver, USA TODAY

This article originally appeared on Sarasota Herald-Tribune: Hurricane Milton surged to Category 4 in less than a day. What is 'rapid intensification'?