Tropical Storm Harvey has maximum sustained winds of 50 mph, with higher gusts, according to the Miami-based National Hurricane Center.
The storm is forecast to strengthen somewhat before its center reaches Belize.
A tropical storm warning is in effect for the coast of Belize and for the Bay Islands of Honduras, which Harvey is predicted to pass near late Friday. A warning is also in effect for the southeastern coast of the Yucatan Peninsula, from Punta Gruesa south to Chetumal, in Mexico.
A tropical storm watch is in effect for the coast of Guatemala and for parts of the coast of Honduras.
A warning means that tropical storm conditions are expected within 36 hours, while a watch means that storm conditions are possible within 48 hours.
As of 8 p.m. ET, Harvey was about 130 miles east of Isla Roatan, Honduras, heading west at 9 mph.
The storm is predicted to dump 3 to 5 inches of rain across Honduras, Guatemala, Belize and the Yucatan Peninsula, with up to 8 inches possible in some places. A storm surge will raise water levels by as much as 1 to 3 feet above normal tide levels along the coast near and to the north of where Harvey makes landfall. (more)