It is moving north at a speed of around 7 m.p.h.
"Michael is expected to affect portions of the Florida Gulf Coast that are especially vulnerable to storm surge, regardless of the storm's exact track or intensity", the Hurricane Center warned.
Gardner said once Michael has moved through the region, it will be dry and brisk, bringing a taste of true fall weather to central North Carolina.
Besides the hurricane watch, a tropical storm watch is in effect from the Suwannee River to Anna Maria Island, including Tampa Bay, as well as from the Alabama-Florida border to the Mississippi-Alabama border. A Category 1 storm packs winds between 74-95 miles per hour, according to the Saffir-Simpson hurricane wind scale.
Elsewhere, outer rain bands from the depression are expected to produce total rain accumulations of 2 to 4 inches across the Florida Keys through Monday.
Current projections suggest Michael could make landfall along the Gulf Coast on Wednesday.
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"Additional strengthening is indicated through 72 hours when the storm is forecast to be near the northern Gulf coast". The North Carolina division of emergency management stated Sunday that the forecast calls for 3 to 5 inches of rain over the next seven days across parts of southeastern North Carolina. Those tropical storm effects will extend inland across southern Georgia and into SC - the storm will pick up speed as it's carried at the tail end of a cold front.
After landfall, Michael is expected to weaken as it tracks quickly northeast, and the forecast track brings the center across southeast Georgia and southeast SC in the Wednesday night and Thursday time period.
The NHC says that Michael is expected to cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline because of a unsafe storm surge and tide. Scott said that as the storm hits the Panhandle, probably at mid-week, it's likely to be a Category 2 hurricane - possibly a 3 - with winds exceeding 100 miles per hour.
The storm was centered about 50 miles (80 kilometers) off the western tip of Cuba, and about 140 miles (220 kilometers) east-northeast of Cozumel, Mexico.
On Sunday, Republican Governor Rick Scott declared a state of emergency in 26 counties in the Florida Panhandle and in Big Bend, ahead of Tropical Storm Michael, which is now making its way through the Gulf of Mexico.
Michael 14th named storm, and now the 7th hurricane of the 2018 Atlantic Hurricane Season. While it will be windy, the chances of us seeing winds of tropical storm force are low.
Michael, which formed near the Yucatan Peninsula on Sunday, is expected to dump 4 to 8 inches of rain - and as much as 12 inches in some areas - on western Cuba before it hits the United States.