A tropical wave is showing signs of organization as it moves over the west-central Caribbean Sea.
A strengthening tropical system in the Caribbean threatens to slam into Mexico's Yucatan Peninsula and could intensify into a hurricane to deliver another blow to the country's east coast later this week. "Slow development of this system is possible during the next several days while it moves generally west-northwestward across the tropical Atlantic at about 15 miles per hour", the forecast advisory said.
While no path of a tropical system is ever set in stone, the longer-range forecasts kept it on a westward track that could steer it into Mexico.
The "Potential Tropical Cyclone" designation allows alerts like tropical storm watches and warnings to be issued for coastal areas with an appropriate amount of time to prepare even though the system is not yet at the threshold to become a named system.
The Air Force is set to send a Hurricane Hunter aircraft into the storm on Monday.
The potential comes from one of two tropical waves now in the Atlantic.
That's not the only thing going in the Atlantic on Sunday.
In the Atlantic, an area of low pressure located about midway between the Cabo Verde Islands and the Lesser Antilles was described as elongated, with showers and thunderstorms that are not well organized.
Forecasters said some slow development is still possible with this system, Invest 99L, in the next few days. There is still a 50 percent chance of it becoming one in the next five.