Tropical Storm Calvin Forms South of Baja California

Tropical Storm Calvin formed over the Eastern North Pacific Ocean south of Baja California on Wednesday morning. At 5:00 a.m. EDT on Wednesday the center of Tropical Storm Calvin was located at latitude 10.4°N and longitude 110.6°W which put it about 725 miles (1170 km) south of the southern tip of Baja California. Calvin was moving toward the west at 16 m.p.h. (26 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (105 km/h). The minimum surface pressure was 1004 mb.

A low pressure system over the Eastern North Pacific Ocean south of Baja California strengthened on Wednesday morning and the U.S. National Hurricane Center designated the system as Tropical Storm Calvin. The distribution of thunderstorms in Tropical Storm Calvin was asymmetrical. Most thunderstorms were occurring in bands in the western side of Calvin’s circulation. Bands in the eastern side of Calvin consisted primarily of showers and lower clouds. The inner end of a rainband wrapped around the southern side of the center of Tropical Storm Calvin. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. The circulation around Calvin was small. Winds to tropical storm force extended out 45 miles (75 km) from the center of Calvin’s circulation.

Tropical Storm Calvin will move through an environment that will be mostly favorable for intensification during the next 36 hours. Calvin will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the southwestern part of an upper level ridge over Mexico and the southwestern U.S. The upper level ridge will produce easterly winds that will blow toward the top of Calvin’s circulation. Those winds will cause vertical wind shear. The wind shear will inhibit intensification, but the shear will not be enough to prevent Calvin from getting stronger. Tropical Storm Calvin will intensify during the next 36 hours. Calvin could strengthen to a hurricane by Friday.

Tropical Storm Calvin will move around the southern part of a subtropical high pressure system over the Eastern North Pacific Ocean. The high pressure system will Calvin toward the west during the next few days. On its anticipated track, Tropical Storm Calvin will move farther away from Mexico. Calvin could move over the Central Pacific Ocean early next week.