MEXICO CITY (AP) — Tropical Storm Lisa strengthened as it pushed across the western Caribbean Tuesday south of the Cayman Islands and was forecast to make landfall, likely as a hurricane, in Central America as early as Wednesday.

The US National Hurricane Center said Lisa had maximum sustained winds of 60 mph (95 kmh) and was moving west at 14 mph (22 kph). The centre of the storm was located about 320 miles (510 kilometres) east of the Honduran island of Roatan.

A hurricane warning was in effect for Roatan and the other Bay Islands of Roatan and Guatemala declared a warning for its entire Caribbean coast.

Lisa was forecast to strengthen to a hurricane by early Wednesday when it crosses over or near the Bay Islands and approach Belize later in the day.

Meanwhile, the Hurricane Center said new Tropical Storm Martin was forming far out in the open Atlantic. It was centred about 550 miles (885 kilometres) east-northeast of Bermuda with maximum sustained winds of 50 mph (85 kph).