Potential Tropical Cyclone Eighteen has formed in the Caribbean, according to the National Hurricane Center.What You Need to Know: Potential Tropical Cyclone Eighteen has formed. It is moving toward the northeast near 7 mph. Sustained winds are currently at 35 mph.At 4 p.m., the National Hurricane Center said that Potential Tropical Cyclone Eighteen is moving toward the northeast near 7 mph. It is expected to turn to the north and then northwest over the next few days. Maximum sustained winds are around 35 mph with higher gusts. The system is expected to become a tropical depression by Sunday night and continue to strengthen. A Hurricane WATCH is in effect for: Cayman IslandsA Tropical Storm WARNING is in effect for: JamaicaRemember Denis Phillips' Rule #7."The NHC track is one that is good news for the Peninsula. A track this far west doesn't mean we won't see some impacts, but those impacts would be lower the farther west it goes. Increasing rain chances are a given. There could be some coastal surge, but the farther west, the lower this risk will be," Phillips said. HURRICANE RESOURCES Hurricane Center Local Forecast Radar