CORRECTION: We incorrectly stated that Irma could be the first major hurricane classified as a category 3 or higher to make U.S. landfall since Hurricane Wilma in 2005. This is incorrect. Hurricane Harvey was a category 4 storm when it made landfall.

"Potentially catastrophic" Hurricane Irma strengthened Tuesday to a Category 5 storm with sustained winds of 185 mph, making it the strongest hurricane in the Atlantic since 2005.

Irma, the strongest hurricane ever recorded in the Atlantic Basin, outside of the Caribbean Sea and the Gulf of Mexico, could slam onto Florida's coast over the weekend. A mandatory evacuation of visitors to the Florida Keys was set to begin at sunrise Wednesday.

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With Texas, along with other areas in the Gulf Coast, still recovering from Hurricane Harvey Irma comes as a one-two punch, but researchers at CSU say that’s not entirely rare.

“We actually have seen quite a few major hurricanes since the last landfalling major hurricane which was Wilma in 2005,” said Dr. Kate Musgrave.

“We're really seeing an active season at the time we would expect to see an active season in the Atlantic,” added research scientist Chris Slocum.

Last year, in 2016, there were 16 named storms, 7 of them hurricanes, with 4 of those being major-- the most since 2012.

The reason the U.S. hasn’t seen a major hurricane make landfall in so long, according to CSU, is simply luck and chance.

“It's been a matter of chance, luck, for the U.S. and just where our large scale steering flows are set up,” Musgrave said.

Large scale flows is a fancy term for high pressure systems. Scientists at the National Weather Service say a high pressure system over Bermuda, commonly known as the

“Bermuda High” shifted ever so slightly east when Category 4 Hurricane Matthew came barreling toward the Eastern Florida Coast last year, causing it to stay offshore and hit the Carolinas as a Category 1 instead.

Similar happening be traced back to 2008 when Hurricane Ike, a Category 4, caused mass evacuations in the Florida Keys, but a small change in the storm's track kept it south, where it continued into the Gulf missing Florida before hitting Texas as a Category 2.

Irma will blast the northern Caribbean with life-threatening flooding rain, damaging winds and rough surf over the next few days, Accuweather said. A similar scenario could then play out somewhere along the Gulf or East coasts of the U.S. this weekend or next week, depending on where Irma tracks.

Gov. Rick Scott warned Floridians to "prepare for the worst." He declared a statewide state of emergency and activated 100 Florida National Guard members to help with storm preparations. The state's full complement of 7,000 Guard members will report for duty Friday.

Scott urged residents to stock up on water and food and to learn the locations of local emergency shelters.

"We don't know what is in store, but we all have to be prepared," Scott said. "When there's an evacuation, listen. In the middle of a hurricane, no one can rescue you."

At 2 p.m. ET Tuesday, the center of Hurricane Irma was located 180 miles east of Antigua, and it was moving west at 14 mph.