Tropical Storm Barry closes in on Louisiana
Tropical Storm Barry is closing in on Louisiana and could trigger severe flooding in and around New Orleans.
With the storm expected to blow ashore by early Saturday as the first hurricane of the season, National Guard troops and rescue crews are posted around the state with boats, high-water vehicles and helicopters.
Utility repair crews are in position and homeowners have sandbagged their property or packed up and left. Tourists have crowded New Orleans' airport in the hope of catching an early flight away from the storm.
National Hurricane Centre director Ken Graham warned: "This is happening. ... Your preparedness window is shrinking. It's powerful. It's strengthening. And water is going to be a big issue."
Forecasters said slow-moving Barry could unload 10 to 20 inches of rain through Sunday across a part of Louisiana that includes New Orleans and Baton Rouge, as well as southwestern Mississippi, with pockets in Louisiana getting 25 inches.
Some low-lying roads near the coast are already covered with water as the tide rose and the storm pushed water in from the Gulf of Mexico.
Barry was expected to roll in as a weak hurricane, just barely over the 74 mph windspeed threshold. But authorities warned people not to be fooled by that.
"Nobody should take this storm lightly just because it's supposed to be a Category 1 when it makes landfall," Louisiana governor John Bel Edwards said.
"The real danger in this storm was never about the wind anyway. It's always been about the rain."
Barry's downpours could prove to be a severe test of the improvements made to New Orleans' flood defences since the city was devastated by Hurricane Katrina in 2005.
The Mississippi River is already running abnormally high because of heavy spring rains and snowmelt upstream, and the ground around New Orleans is soggy because of an 8-inch torrent of rain earlier this week.
The Mississippi is expected to crest on Saturday at about 19 feet in New Orleans, where the levees protecting the city range from about 20 to 25 feet in height. That could leave only a small margin of safety in some places, particularly if the storm were to change direction or intensity.
Scientists say global warming is responsible for more intense and more frequent storms and floods, but without extensive study they cannot directly link a single weather event to the changing climate.
US President Donald Trump declared a federal emergency for Louisiana, authorising the Department of Homeland Security and the Federal Emergency Management Agency to co-ordinate relief efforts.