Tropical Storm Frank formed over the Eastern North Pacific Ocean south of Mexico on Tuesday morning. At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Frank was located at latitude 11.6°N and longitude 102.4°W which put it about 525 miles (845 km) south-southeast of Manzanillo, Mexico. Frank was moving toward the west at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1004 mb.
The circulation around a low pressure system over the Eastern North Pacific Ocean south of Mexico strengthened on Tuesday morning and the National Hurricane Center designated the system as Tropical Storm Frank. The distribution of thunderstorms around Tropical Storm Frank was asymmetrical. Many of the thunderstorms were occurring in bands in the western half of Frank’s circulation. Bands in the eastern half of the tropical storm consisted primarily of showers and lower clouds. An upper level ridge over Mexico and the Eastern North Pacific was producing easterly winds that were blowing toward the top of Frank’s circulation. Those winds were causing moderate vertical wind shear and they were the main reason for the asymmetrical distribution of thunderstorms. Winds to tropical storm force extended out 35 miles (55 km) in the northern side of Tropical Storm Frank. The winds in the southern half of Frank were blowing at less than tropical storm force.
Tropical Storm Frank will move through an environment somewhat favorable for intensification during the next 36 hours. Frank will move over water where the Sea Surface Temperatures are near 29˚C. However, the upper level ridge will continue to produce easterly winds that will cause moderate vertical wind shear. The wind shear will inhibit intensification. Tropical Storm Frank could strengthen gradually during the next 36 hours, if the vertical wind shear does not increase.
Tropical Storm Frank will move south of a high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Frank toward the west during the next 36 hours. On its anticipated track Tropical Storm Frank will move farther away from the west coast of Mexico. Frank will pass south of Baja California later this week.