Updated at 2 p.m. ET
A tropical cyclone in the northwestern Caribbean Sea has been upgraded to a named storm, Tropical Storm Nate. The system is likely to become a hurricane in the next three days and could hit the northern Gulf Coast on Sunday morning, forecasters say.
"Residents along the Gulf Coast from Louisiana through the Florida Panhandle should monitor the progress of this system and heed any advice given by local officials," the National Hurricane Center says.
In an update Thursday, the center said, "Nate is forecast to be near hurricane intensity when it approaches the Yucatan Peninsula late Friday, bringing direct impacts from wind, storm surge, and heavy rainfall."
Nate is showing signs of developing an eyewall. It's also expected to strengthen as it moves over warmer waters on its way to the U.S. coast. But at this point, the National Hurricane Center says, "it is too early to specify the timing, location, or magnitude of these impacts. "
Nate is currently bringing heavy rainfall to Nicaragua and Honduras, as it scrapes along their coasts on a northwest track toward Cancun. The storm has triggered flood warnings in those areas, along with a hurricane watch in Mexico's Yucatan peninsula, from Punta Herrero to Rio Lagartos.
The cyclone has maximum sustained winds of 40 mph, and it's moving northwest at 9 mph. That will change later today, the National Hurricane Center says, when Nate takes a more north-northwestward path and also moves at a faster speed.
By Sunday, Nate's sustained winds are expected to reach 75 mph. While that speed is a far cry from the incredible intensity of recent hurricanes such as Irma and Maria, forecasters say people in Nate's path need to be careful of flash floods and mudslides from its heavy rains.
Powerful winds often attract the most attention and concern regarding cyclones. But it's the water — from both storm surges and rainfall — that's often the most deadly component of a tropical system. The hurricane center warns that Nate will bring 15 to 20 inches of rain to Nicaragua — and that a wide area is at risk, with heavy rainfall expected along the Pacific coast of Central America.
The cyclone's predicted path has shifted to the west since the first NHC advisory went out for Nate's system Wednesday morning. It had once been expected to thread the gap between Mexico and Cuba's west coast, and to make a potential landfall in the Florida Panhandle. The storm is now expected to pass over Mexico's tourism-friendly southern coast, with a potential — and subject to change — landfall forecast along the coast of Louisiana and Mississippi.