(CNN)As Tropical Storm Ian barrels towards Florida -- potentially strengthening to a Category 4 hurricane before slamming the state later this week -- residents are preparing for what could be the Sunshine State's first major hurricane in four years.
Forecasts have also been shifting the storm's track further west, putting the Florida panhandle and nearly the entire western coast of the state as potential risk. Dangerous storm surges, hurricane-force winds and heavy rainfall are likely to follow in the storm's path.
Across Florida, local officials are urging residents to be prepared in the event of flash flooding and damaging winds.
"This is the calm before the storm," Naples Mayor Teresa Heitmann told CNN Saturday. "We experience this kind of adrenaline before a storm and the path could change at any time, but we want our citizens could be ready."
Ian is approximately 395 miles southeast of Grand Cayman and moving west at 13 mph (20 km/h), according to the hurricane center Saturday night, with maximum sustained winds reaching 50 mph (85 km/h).
A hurricane warning is in effect for Grand Cayman, and forecasters are becoming increasingly confident residents in western Cuba will face "life-threatening" storm surge and hurricane-force winds Monday, the hurricane center said. Hurricane and tropical storm watches have been issued for parts of western Cuba.
As the storm approaches Florida, authorities are distributing sandbags and asking Floridians to prepare their property to reduce the risk of hurricane damage and to stock up on supplies like radios, water, canned food and medication. Residents should also pack up important documents and know their evacuation routes.
Prepare for flooding and powerful winds, officials warn
Storm surge -- when the force of a hurricane or storm pushes ocean water onto the shores -- can be one of the greatest threat to life and property from a hurricane.
"We're outside of the cone of uncertainty. We can't relax," Miami-Dade County Mayor Daniella Levine Cava told CNN Saturday. "We know there's always a possibility it will shift. The storm has continued to move westward. This is the time everyone should make sure they have a plan."
Cava urged residents to make sure they have enough food and water and check their storm surge planning zone.
"We're very hopeful that even with a major rain event, we'll be able to manage it," Cava said. "We're on standby. We have extra pumps, and we've worked with the South Florida Water Management District to lower canal levels."
Miami-Dade County is preparing its "extensive shelter system," including for those fleeing the Florida Keys if evacuations are ordered there.
In Naples, Heitmann said she's already seeing lines at the gas stations as residents brace for the potential hurricane.
"They're taking it serious, and I encourage those that are not to always take a storm serious, because you can never estimate where that storm might turn. And we need to be prepared and if it's not coming directly for us, it might have strong winds," Heitmann said.
In Sarasota, authorities are checking on generators, planning with local police, trying to estimate how much flooding is possible and warning residents to be prepared, Mayor Erik Arroyo told CNN.
"Don't underestimate the dangers that come with gusts, with storm surges, with flooding, especially us being a coastal city. So we're telling them to go now, be prepared early," Arroyo said.