KINGSTON, Jamaica — A tropical storm warning and a hurricane watch remain in effect as Tropical Storm Melissa moves slowly across the Caribbean Sea south-southeast of Jamaica.

This means tropical storm conditions are a possible threat to Jamaica within 36 hours and hurricane conditions are likely to pose a threat within 48 hours.

At 4:00 pm, the centre of Tropical Storm Melissa was located near latitude 15.6 degrees north, longitude 75.5 degrees west. This is about 270 kilometres (170 miles) south-southeast of Morant Point, Jamaica or about 300 kilometres (185 miles) south-southeast of the capital Kingston.

Tropical Storm Melissa is moving very slowly toward the north-northwest near four km/h (two mph). A slow forward speed and northward motion is forecast during the next couple of days, followed by a sharp westward turn over the weekend.

Maximum sustained winds are near 75 km/h (45 mph) with higher gusts. Gradual strengthening is forecast during the next day or so, followed by rapid intensification this weekend. Melissa is forecast to become a hurricane by Saturday and a major hurricane by Sunday.

Satellite and radar imagery indicate that the heavy showers and thunderstorms associated with the core of Tropical Storm Melissa are located approximately 200 kilometres southeast of Jamaica and are slowly moving toward the island.

Based on the current forecast, Tropical Storm Melissa is expected to continue moving toward Jamaica before turning westward on Saturday and passing over the waters south of the island. As the system approaches, showers and thunderstorms are forecast to begin affecting the island late Thursday evening or by Friday. Periods of moderate to heavy rainfall are expected to continue through the weekend, leading to an increased risk of flooding and landslides, especially in low-lying, flood prone and hilly areas.

Due to Melissa’s slow movement, strong, gusty winds, possibly reaching tropical storm strength, are expected to gradually develop on Friday, continuing into the weekend. These winds will initially affect eastern and southern parishes, before gradually spreading across the remainder of the island. Winds reaching hurricane strength are possible over sections of eastern parishes as early as Saturday, as Tropical Storm Melissa continues to move closer to Jamaica.

Marine interests should expect widespread heavy showers and thunderstorms, accompanied by tropical-storm-force winds tonight and continuing through the weekend. Winds reaching hurricane strength are likely on Saturday, particularly over southern and eastern offshore waters, as Tropical Storm Melissa moves closer to the island.

All small craft operators including fishers from the cays and banks should by now be in port and are urged to complete their necessary safety precautions without delay.

The Meteorological Service continues to closely monitor the progress of Tropical Storm Melissa.