Tropical Storm Melissa stalled over the Caribbean Sea southeast of Jamaica on Wednesday. At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Melissa was located at latitude 14.4°N and longitude 74.3°W which put the center about 300 miles (480 km) south-southeast of Kingston, Jamaica. Melissa was moving toward the west-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 1000 mb.
A Hurricane Watch is in effect for the southern coast of Haiti from the border with the Dominican Republic to Port Au Prince.
A Tropical Storm Watch is in effect for Jamaica.
Tropical Storm Melissa stalled southeast of Jamaica as easterly winds in the lower levels of the atmosphere and westerly winds in the upper levels competed to push the tropical storm. The vertical wind shear was also affecting the structure of Melissa’s circulation. Thunderstorms continued to develop in bands in the eastern side of Tropical Storm Melissa. Bands in the western side of Melissa’s circulation still consisted primarily of showers and lower clouds. Storms near the center of Melissa generated upper level divergence that pumped mass away to the east of the tropical storm. The removal of mass in the upper levels was nearly equal to the inflow of mass in the lower levels of the atmosphere. So, the surface pressure did not change much on Wednesday.
The vertical wind shear also caused the distribution of wind speeds in Tropical Storm Melissa to be asymmetrical. Winds to tropical storm force extended out 115 miles (185 km) in the eastern half of Melissa’s circulation. Winds to tropical storm force extended out 70 miles (110 km) in the northwestern quadrant of Tropical Storm Melissa. The winds in the southwestern quadrant of Melissa’s circulation were blowing at less than tropical storm force.
Tropical Storm Melissa will move through an environment that is marginally favorable for intensification during the next 24 hours. Melissa will move over water where the Sea Surface Temperatures are near 30°C. It will move under the southeastern part of an upper level trough that is over Cuba. The upper level trough will produce westerly winds that will blow toward the top of Melissa’s circulation. Those winds will produce moderate vertical wind shear. The moderate vertical wind shear will inhibit intensification, but the wind shear may not be enough to prevent intensification. Tropical Storm Melissa could intensify a little during the next 24 hours.
Tropical Storm Melissa will move around the western end of a high pressure system that is over the Atlantic Ocean. The high pressure system will steer Melissa slowly toward the northwest during the next 24 hours. On its anticipated track, Tropical Storm Melissa will move slowly toward Jamaica.
