Tropical Depression Thirteen intensified into Tropical Storm Lisa west of the Cape Verde Islands on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Lisa was located at latitude 16.4°N and longitude 31.0°W which put it about 465 miles (750 km) west of the Cape Verde Islands. Lisa was moving toward the northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 45 m.p.h. (70 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1004 mb.
The degree of organization of the circulation of Tropical Storm Lisa depends on the level of the atmosphere. The low level circulation is not well organized. There is a broad center of circulation, but it does not have a tight core of thunderstorms. Most of the thunderstorms are east of the center of circulation. There are also several fragmented rainbands in the eastern half of the circulation. There are only lower clouds and a few showers in the western half of the circulation. However, the circulation is more well organized in the upper levels. The thunderstorms in the eastern half of the circulation are generating upper level divergence which is pumping out mass toward the northeast and toward the northwest. It appears that the circulation could be tilted toward the northeast with height.
The environment around Tropical Storm Lisa is marginal for intensification. Lisa is moving over water where the Sea Surface Temperature (SST) is near 28°C. However, an upper level trough north of Lisa is producing southwesterly winds which are blowing across the tropical storm. The winds are causing moderate vertical wind shear, which probably contributed to the asymmetrical distribution of thunderstorms. Tropical Storm Lisa could intensify somewhat on Wednesday, if the upper level winds diminish. When Lisa moves farther north later this week, it will move over cooler SSTs and into a region where the upper level winds are stronger. Less energy in the upper ocean and more vertical wind shear will cause Tropical Storm Lisa to weaken later this week.
Tropical Storm Lisa is moving northwest toward a section of the subtropical ridge which is weaker. Lisa is expected to continue to move in that general direction for the next several days. Tropical Storm Lisa will move farther into the middle of the Atlantic Ocean and it will not threaten any land areas this week.