Tag Archives: Tropical Depression Seven

Tropical Depression Seven Forms East of the Leeward Islands

Tropical Depression Seven formed east of the Leeward Islands on Wednesday morning. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Seven was located at latitude 16.6°N and longitude 49.6°W which put it about 805 miles (1300 km) east of the Leeward Islands. The tropical depression was moving toward the west at 14 m.p.h. (13 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1009 mb.

A low pressure system over the Atlantic Ocean east of the Leeward Islands strengthened on Wednesday morning and the National Hurricane Center designated the system as Tropical Depression Seven. The distribution of thunderstorms in Tropical Depression Seven was asymmetric. Many of the thunderstorms were occurring in bands in the eastern half of the tropical depression. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Storms in the eastern half of the circulation generated upper level divergence that pumped mass away from the tropical depression.

Tropical Depression Seven will move through an environment somewhat favorable for intensification during the next 36 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western part of an upper level ridge over the tropical Atlantic Ocean. The ridge will produce southerly winds that will blow toward the top of the tropical depression. Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but Tropical Depression Seven is likely to strengthen to a tropical storm.

Tropical Depression Seven will move around the southern side of the subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer the tropical depression toward the west during the next few days. On its anticipated track Tropical Depression Seven could approach the Leeward Islands on Friday afternoon. It could be a tropical storm when it approaches those islands.

Tropical Depression Seven Forms East of Windward Islands

Tropical Depression Seven formed east of the Windward Islands on Tuesday afternoon.  At 5:00 p.m. EDT on Tuesday the center of Tropical Depression Seven was located at latitude 9.8°N and longitude 40.4°W which put it about 1420 miles (2285 km) east of the southern Windward Islands.  It was moving toward the west-northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1009 mb.

An area of low pressure between the coast of Africa and the Windward Islands exhibited more organization on Tuesday afternoon and the National Hurricane Center designated the system as Tropical Depression Seven.  The circulation around Tropical Depression Seven was still organizing.  Bands of showers and thunderstorms were developing and the bands were revolving around the center of circulation.  Storms near the center started to generate upper level divergence which was pumping mass away from the tropical depression.

Tropical Depression Seven will move through an environment favorable for intensification during the next several days.  The depression will move over water where the Sea Surface Temperature is near 29.5°C.  It will move through a region where the upper level winds will be weak and there will be little vertical wind shear.  Tropical Depression Seven is likely to strengthen into a tropical storm during the next 24 hours.

Tropical Depression Seven will move south of a subtropical high pressure system over the Atlantic Ocean.  The high will steer the depression toward the west during the next few days.  On its anticipated track Tropical Depression Seven could approach the Windward Islands on Saturday.

Elsewhere, a tropical wave over the eastern Gulf of Mexico was designated as Invest 91L on Tuesday afternoon.  At 2:00 p.m. EDT on Tuesday the center of Invest 91L was located at latitude 25.2°N and longitude 84.7°W which put it about 200 miles (320 km) west of Key West, Florida.  It was moving toward the west-northwest at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts: to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1014 mb.  The National Hurricane Center indicated that there was a 40% probability of the formation of a tropical depression.