ORLANDO, Fla. (AP) -- A tropical storm that rapidly formed off Mexico's Yucatan Peninsula has gained new strength and could become a dangerous Category 2 hurricane with an expected midweek strike on the Gulf Coast in the Florida Panhandle, forecasts say.
Florida Gov. Rick Scott issued an order for a state of emergency for 26 counties to rush preparations in the Florida Panhandle and the Big Bend area, freeing up resources and activating 500 members of the Florida National Guard.
"This storm will be life-threatening and extremely dangerous," Scott said Sunday after receiving a briefing at the State Emergency Operations Center. He warned that storm surge could affect areas of Florida not in the storm's direct path.
Michael emerged Sunday as a tropical storm with winds of up to 50 mph (85 kph). But within hours Sunday it had gained more punch and its top sustained winds clocked in at 60 mph (95 kph) by late Sunday evening. The storm is expected to gain hurricane status by Monday night or Tuesday as its center moves over the Yucatan Channel and then crosses the Gulf of Mexico, nearing the Florida Panhandle coast by Wednesday.
The storm was located by 2 a.m. ET Monday about 105 miles (170 kilometers) east-southeast of Cozumel, Mexico, and moving to the north at about 4 mph (6 kph). Tropical storm winds extended out 170 miles (275 kilometers), primarily to the northeast and southeast of the storm's center.
Forecasters advised residents along the northeastern and central U.S. Gulf Coast to monitor the storm's progress.
The north Florida city of Tallahassee on Sunday opened two locations where residents could get sandbags in case of flooding.
"While the impacts are still uncertain, our area could experience increased wind activity and heavy rainfall, which could cause localized flooding and downed trees," Tallahassee officials said in a statement.
Tallahassee Mayor Andrew Gillum, who is the Democratic nominee for governor, had planned to campaign in South Florida Monday and Tuesday, but he said he would return to Tallahassee to help with storm preparations.
The city of Pensacola tweeted to residents, "Be sure you have your emergency plan in place."
A tropical storm warning was in effect for the Cuban provinces of Pinar del Rio and the Isle of Youth as well as the coast of Mexico from Tulum to Cabo Catoche. A warning indicates tropical storm conditions are expected, in this case, within 24 hours.
The hurricane center warned that the storm could produce a foot (30 centimeters) of rain in western Cuba, potentially triggering flash floods and mudslides in mountainous areas. The rains in Cuba's west were expected to begin Sunday night and continue Monday.
An Air Force hurricane hunter airplane was sent into the storm to investigate, the hurricane center said.
Michael is the 13th named storm of the 2018 hurricane season, according to hurricane center spokesman Dennis Feltgen.