Already, emergencies have been declared in two states – all of Florida, as well as eastern and central North Carolina. In both states, the decision was made because governors wanted to make resources available for what may become a large-scale preparation if Matthew were to threaten.
Here's the latest on how preparations are going.
Florida
Florida Gov. Rick Scott said during a press conference on Monday that he had declared a statewide of emergency because of expected impacts from Matthew.
On Sunday, Scott said that he was taking no chances with the storm, calling it "catastrophic." He is urging residents to be prepared, according to NBC News.
"If it hits our state, we could see impacts that we have not seen in many years," Scott said.
Scott's spokeswoman, Jackie Schutz, said on Monday that the governor had canceled Tuesday's Cabinet meeting to visit the state's emergency operations centers along Florida's east coast, according to the AP.
The U.S. Coast Guard issued an advisory to boaters in southeastern Florida Monday, saying they should begin to prepare for Hurricane Matthew.
While ports and facilities remain open to commercial traffic, all oceangoing vessels and barges greater than 500 gross tons "should make plans for departing the port," the Coast Guard said in its press release.
Pleasure-boat owners are being advised to seek safe harbor.
North Carolina
On Monday, Gov. Pat McCrory declared a state of emergency for 66 counties in central and eastern North Carolina, according to the Associated Press.
McCrory said at a news conference that he made the declaration at the request of North Carolina Agriculture Commissioner Steve Troxler.
According to the governor, the declaration will help farmers clear their crops by lifting truck weight restrictions and hours of service. This will allow farmers to get their harvest to market ahead of any possible impacts from the hurricane.
The governor said he didn't want farmers to wait until Thursday to begin work if the storm is close to North Carolina.
South Carolina
The South Carolina Emergency Management Division issued a press release Sunday informing the public it has recommended the state's emergency response team review disaster preparedness plans, according to the AP.
Officials in Horry, Beaufort and Charleston counties say they're on alert status, noting that the storm's path is too uncertain to rule out any possibility.
Kim Stenson, director of the South Carolina Emergency Management Division, held conference calls this weekend with county emergency managers, emergency response teams and local National Weather Service offices.
On Monday, Hilton Head Island is suspending work on a $21 million dollar project to dredge sand from the ocean and rebuild the beach on the resort island on the state's southern tip until the storm passes, according to AP.