Tropical Depression 2E intensified into Tropical Storm Agatha on Saturday morning. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Agatha was located at latitude 15.6°N and longitude 118.9°W which put it about 775 miles (1245 km) southwest of the southern tip of Baja California. Agatha was moving toward the west-northwest at 12 m.p.h. (19 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 1005 mb.
The upper level winds blowing over the top to Tropical Depression 2E weakened and the vertical wind shear decreased. Less vertical wind shear allowed thunderstorms on the northwestern side of the circulation to wrap around the southern side of the center. With the center of circulation embedded near the main area of thunderstorms the National Hurricane Center named the system Tropical Storm Agatha. Agatha is a small system and tropical storm force winds only extend out about 45 miles (75 km) from the center.
Agatha has a limited period in which to intensify further. It is currently moving over water where the Sea Surface Temperature (SST) is near 28°C. However, Agatha is moving toward cooler SSTs where there will be less energy to drive the circulation. In addition, there is much drier air north and west of the tropical storm. Since there is little vertical wind shear, Agatha could intensify during the next 12 to 24 hours. It will start to weaken when it moves over the cooler SSTs.
A ridge of high pressure north of Agatha is steering the tropical storm toward the east-northwest and that general motion is expected to continue for another day or two. Agatha currently poses no threat to land.
Agatha was named on July 2. This is the latest date for the naming of the first tropical storm over the Eastern North Pacific since Ava was named in 1969.
After a prolonged period of relatively quiet weather over the Eastern North Pacific Ocean, a tropical depression formed southwest of Baja California. At 11:00 p.m. EDT on Friday the center of Tropical Depression 2E (TD2E) was located at latitude 14.7°N and longitude 116.7°W which put it about 730 miles (1170 km) southwest of the southern tip of Baja California. TD2E was moving toward the west-northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1007 mb.
A tropical wave over the Eastern North Pacific Ocean developed a well defined low level circulation and the National Hurricane Center classified the system as Tropical Depression 2E on Friday night. Although the structure of the low level wind field is symmetrical, most of the thunderstorms are located northwest of the center of circulation. An upper level ridge north of the depression is generating easterly winds over the top of the circulation. The vertical wind shear is causing the asymmetrical distribution of the thunderstorms.
The environment around Tropical Depression 2E is marginal for intensification because there are both positive and negative factors. TD2E is moving over water where the Sea Surface Temperature is near 29°C. So, there is plenty of energy in the upper ocean to support intensification. However, the air to the west of the tropical depression is very dry, which will limit the growth of thunderstorms and the formation of rain bands in that part of the system. In addition moderate vertical wind shear will also inhibit intensification. Tropical Depression 2E could intensify during the weekend and it has a chance to become the first named storm of the 2016 Eastern Pacific hurricane season. However, the potential for intensification is limited.
The ridge to the north of TD2E is expected to continue to steer it toward the west-northwest during the next several days. Tropical Depression 2E poses no threat to land during the next five days.