(NewsNation) — Hurricane Ian’s extremely dangerous eyewall is making its way onshore as a Category 4 hurricane over Florida’s west coast, according to the National Hurricane Center’s (NHC) latest update.

Florida Gov. Ron DeSantis said it is now unsafe to evacuate Florida’s west coast and that all residents should shelter in place.

At 11 a.m. ET, Air Force and NOAA hurricane hunters located the eye of the hurricane about 45 miles west of Naples, Florida, moving toward the north-northeast near 9 mph.

Maximum sustained winds remain at 155 mph, meaning it is only 2 mph short of intensifying to a Category 5 storm (157 mph), with higher wind gusts, NHC said. The storm is expected to bring life-threatening storm surges, rain and power outages throughout Florida.

“It is now a Category 4 hurricane with maximum sustained winds of up to 155 mph — that is knocking on the door of a Category 5 storm,” DeSantis said at a news conference Wednesday morning.

More than 200,000 Floridians are without power, according to poweroutage.us.

“Don’t go outside in the eye of the storm,” DeSantis warns. “It’s still dangerous. There is actually a calmness if the center of the hurricane is right over you … even if it seems calm, wait to make sure that the storm has actually passed.”

The highest risk counties are from Collier County up to Sarasota County, and the most recent track has the storm making landfall in Charlotte County.

“If you are in any of those counties, it is no longer possible to safely evacuate,” DeSantis said. “It’s time to hunker down and prepare for this storm. This is a powerful storm that should be treated like you would treat if a tornado was approaching your home.”

There are over 200 shelters open in just the southwest Florida region alone.

Winds and rain have begun intensifying a day after Ian battered the western tip of Cuba, bringing down the electricity grid and leaving the entire island without power.

Ian’s forward movement slowed over the Gulf, enabling the storm to grow wider and stronger. A hurricane warning covering roughly 220 miles of the state included Fort Myers as well as Tampa and St. Petersburg, which could get their first direct hit by a major hurricane since 1921.

Forecasters said the storm surge could reach 12 to 16 feet if it peaks at high tide. Rainfall near the area of landfall could top 18 inches.

Airports in Tampa, St. Petersburg and Key West closed. Disney World theme parks and Sea World in Orlando all closed ahead of the storm.

Miami-Dade County suspended countywide transit services including Metrobus, Metrorail, Metromover and Special Transportation Services on Wednesday morning.

Tolls have been suspended along interstates to allow for faster evacuations, and bridges will be closed when certain wind speeds are met, officials said.

White House press secretary Karine Jean-Pierre said Tuesday night President Joe Biden and DeSantis discussed ways the federal government is helping Florida prepare for the hurricane and later committed to continue providing a closely coordinated storm response.

As of Tuesday night, at least 5,000 Florida Guardsmen have been activated and pre-positioned at armories across the state.

So far, 26 school districts have been closed, and more are expected to close as the storm approaches.

Residents waited upward of four hours to fill sandbags at one of three locations. Grocery store lines reached down the streets as many prepared for the storm.

Biden also declared an emergency, authorizing the Department of Homeland Security and the Federal Emergency Management Agency, or FEMA, to coordinate disaster relief and provide assistance to protect lives and property.

The president postponed a scheduled Sept. 27 trip to Florida due to the storm and NASA decided to forgo a planned Tuesday launch opportunity for its new moon rocket.

NewsNation affiliate and the Associated Press contributed to this report.