Hurricane Milton tracker: Category 5 storm an 'extremely serious threat' to Florida

The St. Pete-Clearwater International Airport, just outside of Tampa, Florida, will close at 12:30 p.m. Tuesday and stay shut on Wednesday and Thursday.

"The airport is in a mandatory evacuation zone and is not a public shelter," airport officials tweeted. "Prepare and stay safe."

Tampa International Airport will suspend operations beginning at 9 a.m. Tuesday and stay closed "until it can assess any damage after the storm," airport officials said.

The Orlando International Airport will close Wednesday morning and reopen as soon as it's safe, officials said.

The Sarasota Bradenton International Airport will close at 4 p.m. Tuesday.

Federal Emergency Management Agency Administrator Deanne Criswell, who has been on the ground in North Carolina helping organize relief efforts in the wake of Hurricane Helene, will travel to Florida on Monday to meet with leaders ahead of Hurricane Milton.

Criswell will then return to North Carolina. FEMA senior leader and regional administrator Willie Nunn will stay in Florida to coordinate the response to Hurricane Milton.

Crews on the ground in Florida include "six FEMA Incident Management Assistance Teams, five FEMA Urban Search & Rescue teams, three U.S. Coast Guard Swift Water Rescue teams, four HealthCare System Assessment Teams, two U.S Army Corps of Engineers (USACE) temporary power teams, USACE debris experts, Environmental Protection Agency (EPA) and wastewater experts, 300 ambulances and 30 High Water Vehicles with ladders from the Department of Defense," FEMA said in a statement.

-ABC News’ Chad Murray

Milton, currently a Category 4 hurricane, is forecast to strengthen to a Category 5 within a few hours.

Milton is expected to weaken to a Category 3 hurricane by the time it approaches Florida Wednesday night. Landfall is expected late Wednesday or early Thursday.

Storm surge is a major threat.

A record-breaking storm surge of 8 to 12 feet is forecast for the Tampa Bay area. This comes as Floridians are still cleaning up from the record-setting 6 to 8 feet of storm surge that was just unleashed by Hurricane Helene.

Flooding is also expected.

Rain from a separate system is already drenching Fort Lauderdale and Miami on Monday and Tuesday, and then when Milton hits, more heavy rain is forecast from Tampa to Jacksonville. Locally, up to 15 inches of rain is possible in parts of Florida over the next three days.

A hurricane watch has been issued for Tampa, Orlando and Fort Myers.

-ABC News’ Max Golembo

The University of Florida is canceling classes on Wednesday and Thursday due to Hurricane Milton. The school plans to reopen on Friday morning, officials said.