A state of emergency has been declared in the Central American countries after Nate left 22 people dead and more than 20 others missing as it rolled through the region.
Heavy rains, landslides and floods have left roads blocks and forced thousands to leave their homes as the tropical storm, which is expected to become a hurricane by the time it reaches the US mainland on Sunday, slowly moves towards Mexico.
At least eight people, including two children, died when the storm hit Costa Rica yesterday, with the horrendous weather conditions leaving more than 400,000 people without running water.
Another 17 people are still missing and more than 7,000 were forced to leave their homes and take refuge in shelters.
As the storm moved northwards and hit Nicaragua it claimed the lives of another 11 people, while seven others are still missing and thousands were forced to leave their homes as water levels rose.
The National Hurricane Centre (NHC) is predicting as much as 15 inches of rainfall over the coming hours in southern Honduras and western Nicaragua.
Two youths drowned in a river as Nate smashed into Nicaragua as a result of the sudden swell caused by the river, while another man was killed in a mudslide in El Salvador.
Extensive damage has been caused to infrastructure in Nicaragua and the vice president Rosario Murillo warned people to avoid dangerous waters as he addressed the nation on local radio.
He said: "Sometimes we think we think we can cross a river and the hardest thing to understand is that we must wait.
"It's better to be late than not to get there at all."
Nate was expected to move off the eastern coast of Honduras at 23:00 ET (03:00 GMT) on Thursday, according to the NHC.
It is expected to be near hurricane intensity when it approaches Mexico's Yucatan Peninsula later on Friday and up to eight inches of rain has been predicted for the region.
Huge torrents of water surge down the Tiribi river in Costa Rica
Dogs stand near a road left badly damaged after Nate struck Costa Rica on Thursday
A state of emergency has been declared for 29 Florida counties and the city of New Orleans, which was declared off-limits to residents when Hurricane Katrina ravaged the city in 2005.
Floodwalls and levees constructed by the US Army Corps of Engineers failed below design specifications and 80 per cent of the city flooded, in what the University of California Berkeley's Dr. Raymond B. Seed called "the worst engineering disaster in the world since Chernobyl”.
The scale of the damage forced many people to leave New Orleans permanently, and more than 1,500 were killed by the devastating hurricane.
The city’s mayor, Mitch Landrieu, tweeted: "There is no need to panic. Be ready and prepare. Get a plan. Prepare to protect your personal property."
Flash floods this summer exposed weaknesses in New Orleans’ drainage system, forcing officials to make last minute attempts to get the city ready for the expected rise in water levels.
A hurricane watch is also in effect for the city, according to the National Hurricane Centre (NHC), with as much as a foot of rain expected in some areas.
NHC spokesman Dennis Feltgen said: "The threat of the impact is increasing, so folks along the northern Gulf Coast should be paying attention to this thing.”
Meteorologist Brittney Bryant tweeted: “Tropical Storm Nate is expected to make landfall just east of New Orleans on Sunday morning as a Cat 1 hurricane.”
Another meteorologist, Eric Holthaus, warned Nate could undergo “rapid strengthening” before hitting the city.
He tweeted: “Nate is expected to make landfall near New Orleans as a hurricane on Sunday. Conditions ripe for rapid strengthening, so watch it closely.”