Tropical Storm Sally has strengthened off the west coast of Florida and is poised to become a category two hurricane, bringing the threat of dangerous storm surges and high winds to the US Gulf Coast.
The storm track is disrupting oil production in the US Gulf of Mexico for a second time in less than a month. The National Hurricane Center says the storm is likely to reach hurricane strength on Monday and approach the north-central Gulf Coast late on Monday and Tuesday.
Hurricane conditions are expected by early Tuesday from Grand Isle, Louisiana to Ocean Springs, Mississippi, including New Orleans.
Louisiana Governor John Bel Edwards said he had spoken earlier in the day to US President Donald Trump and had also requested a federal declaration of emergency in advance of Sally.
At 4pm on Sunday (6am on Monday AEST), Sally was about 265km south of Panama City, Florida, and heading west-northwest with top sustained winds of 95km/h.
Sally is expected to become a category two hurricane with 161km/h winds by the time it makes landfall in southeast Louisiana on Tuesday, the US National Weather Service says.
The storm follows Laura, which rampaged across the Gulf of Mexico three weeks ago and grew into a category four hurricane with 240km/h winds. It shut hundreds of offshore oil facilities, levelled coastal Louisiana towns and left residents of Louisiana and Texas without power for weeks.
Further off in the Atlantic Ocean, Hurricane Paulette is moving closer to Bermuda and is expected to move near or over the island on Monday morning.
It is carrying top sustained winds of 120km/h and is expected to strengthen during Sunday.
Australian Associated Press
