Hurricane Irma grew to wind forces of 120 miles per hour by 8 a.m. on Monday with at least one model predicting that the storm will hit south Florida on Sept. 11.
Irma intensified to a Category 3 storm on Sunday and is expected to gain strength on Monday and Tuesday.
While there is no definitive prediction whether Irma will reach the U.S., a storm forecast model developed by the American National Oceanic and Atmospheric Administration and mapped by Ventusky.com shows the hurricane hitting south Florida on Sept. 11 with winds reaching 119 miles per hour. That prediction was based on weather data available at 11 a.m. Monday.
The storm was moving west towards the Caribbean at 14 miles per hour as of the 8 a.m. advisory by the National Hurricane Center. At the time of the advisory, Irma was 610 miles from Leewards Islands with winds felt up to 30 miles from the eye of the storm.
Hurricane watches have been issued for Antigua, Barbuda, Anguilla, Montserrat, Saint Kitts and Nevis, Saba, St. Eustatius, Sint Maarten, Saint Martin and Saint Barthelemy.
Meanwhile, NHC advised U.S. Virgin Islands, Puerto Rico, Dominican Republic, Haiti, and Leeward Islands to monitor Irma's progress.
Residents in South Florida were seen buying hurricane supplies as Hurricane Irma churns the Atlantic Ocean.
It's unclear what path Irma will take, but just in case, Florida residents have been encouraged to go get supplies by the middle of the week in case the hurricane hits Florida, CBS12 in South Florida reported.
Jacob Tibbs, a Home Depot manager in Palm Beach County, noted that "shoppers are already coming into the hardware store, picking up hurricane items: from generators to water," CBS12 reported.
He recommended that people get basic supplies such as canned goods, water, flashlights, and batteries.
If people wait until the last minute, they might not be able to buy up basic supplies in time if stores run out.
According to local news website TCPalm.com, residents in Vero Beach and the rest of Florida's Treasure Coast were seen grabbing hurricane supplies.
A journalist with TCPalm also saw "several store customers wheeled by with shopping carts containing 5-gallon gasoline cans," the report stated, adding that another man was on the "phone, trying to get help taking home a large Storm Responder electrical generator he purchased at Lowe's home improvement store on Sunday."
"You can't take a chance," said David Yates, a 42-year-old automotive technician, told the website as he was buying supplies, including propane canisters, chain saw supplies, and mosquito repellent.
"I can't do this last minute," Evon Hardin, a shopper, told the website as she removed packs of batteries.
Epoch Times contributed to this report.