Marco strengthened into a hurricane over the Gulf of Mexico on Sunday on its way toward the Louisiana coast, according to data from an Air Force Reserve hurricane hunter aircraft.
Tropical Storm Laura, which the hit the Dominican Republic and Haiti, is also expected to develop into a hurricane and is headed toward the U.S. coast.
Laura could make landfall from Texas to Florida's Gulf Coast by Wednesday afternoon and Marco could hit Louisiana or Mississippi Monday afternoon, according to National Hurricane Center projections.
The National Hurricane Center warned of potentially life-threatening storm surge and high winds along the Gulf Coast as Hurricane Marco approaches. A storm surge of up to 6 feet was forecast for some areas on the Louisiana and Mississippi coast.
Louisiana Gov. John Bel Edwards declared a state of emergency on Friday and requested the Trump administration to grant federal emergency status to the state in preparation for the developing storms. Mississippi Gov. Tate Reeves also declared a state of emergency and warned residents that space in evacuation shelters would be limited because of Covid-19.
This year's hurricane season is on pace to become one of the worst in recorded history, in part because of hotter-than-average sea surface temperatures in the tropical Atlantic Ocean and Caribbean Sea.
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The warmer ocean temperatures are driven by climate change, which has triggered more intense and frequent disasters like hurricanes, wildfires and heatwaves. California is currently battling more than 500 fires during the worsening coronavirus pandemic.
"We are in unprecedented times," Reeves said at a news conference Saturday. "We are dealing with not only two potential storms in the next few hours, we are also dealing with Covid-19."
The hurricane season runs from June 1 to Nov. 30 and is forecast to have 19 to 25 named storms, with 7 to 11 of those storms expected to develop into hurricanes, according to the National Oceanic and Atmospheric Administration. NOAA forecasts there will be 3 to 6 major hurricanes with winds greater than 111 miles per hour.