TD 31 Strengthens to Tropical Storm Iota

Former Tropical Depression Thirtyone strengthened to Tropical Storm Iota on Friday afternoon. At 4:00 p.m. EST on Friday the center of Tropical Storm Iota was located at latitude 13.8°N and longitude 73.8°W which put it about 335 miles (540 km) south-southeast of Kingston, Jamaica. Iota was moving toward the west-southwest at 3 m.p.h. (5 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1006 mb.

The low level circulation around former Tropical Depression Thirtyone appeared to reform a little farther to the southeast near a band of showers and thunderstorms on Friday afternoon. Based on data from satellites the National Hurricane Center upgraded the depression to Tropical Storm Iota. The circulation around Iota was still organizing. A band of thunderstorms wrapped about three quarters of the way around the center of circulation on the southern, eastern and northern sides of the center. Other bands of showers and thunderstorms were revolving around the center of the Tropical Storm Iota. Storms near the center generated upper level divergence which pumped mass away to the north and east of the tropical storm. Winds to tropical storm force extended out 100 miles (160 km) on the eastern side of Iota. The winds on the western side of Iota were blowing at less than tropical storm force.

Tropical Storm Iota will move through an environment favorable for intensification during the weekend. Iota will move over water where the Sea Surface Temperature is near 29°C. An upper level trough over the western Caribbean Sea will produce southwesterly winds which blow toward the top of Iota during the next 12 hours. Those winds will cause vertical wind shear, but the shear will not be strong enough to prevent Tropical Storm Iota from becoming more organized. The upper level trough will move westward away from the depression and the wind shear will decrease during the weekend. Tropical Storm Iota is likely to strengthen more rapidly after an inner core is formed. Iota could rapidly intensify into a hurricane on Saturday and it could strengthen to a major hurricane by Sunday.

Tropical Storm Iota will move south of a high pressure system over the western Atlantic Ocean. The high will steer Iota toward the west during the next several days. On its anticipated track Iota could approach the coast of Nicaragua on Sunday. It will likely be a hurricane at that time and it could be a major hurricane. Nicaragua and Honduras are still trying to cope with floods and other damage caused by Hurricane Eta a few days ago. Another hurricane could have catastrophic consequences for that region.

Elsewhere over the Atlantic Ocean, Tropical Storm Theta Passed south of the Azores. At 4:00 p.m. EST on Friday the center of Tropical Storm Theta was located at latitude 31.9°N and longitude 22.6°W which put it about 490 miles (785 km) south-southeast of the Azores. Theta was moving toward the east at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 993 mb.