Tropical Storm Cosme formed southwest of Baja California on Saturday. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Cosme was located at latitude 15.6°N and longitude 115.7°W which put it about 630 miles (1015 km) southwest of the southern tip of Baja California. Cosme was moving toward the west-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 1001 mb.
The National Hurricane Center (NHC) determined on Saturday that a distinct center of circulation had developed in a broader area of lower pressure and NHC designated the system as Tropical Storm Cosme. The distribution of thunderstorms around Tropical Storm Cosme was asymmetrical. The stronger thunderstorms were occurring in bands in the eastern half of the circulation. Bands in the western half of the circulation consisted primarily of showers and lower clouds. An upper level trough near Baja California was producing strong southwesterly winds which were blowing across the top of the circulation. Those winds were causing strong vertical wind shear and they were probably the reason for the asymmetrical distribution of thunderstorms. Winds to tropical storm force extended out about 150 miles (240 km) from the center of circulation.
Tropical Storm Cosme will move through an environment that is not favorable for significant intensification. Cosme will move over water where the Sea Surface Temperature is near 26°C. The upper level trough will continue to produce southwesterly winds that will blow toward the top of Tropical Storm Cosme. The upper level winds are likely to weaken somewhat, but they will continue to cause vertical wind shear. Tropical Storm Cosme could intensify a little during the next 24 hours, but it is not likely to strengthen significantly.
Tropical Storm Cosme will move south of a subtropical high pressure system over Eastern North Pacific Ocean. The high will steer Cosme toward the west-northwest. On its anticipated track Tropical Storm Cosme is forecast to remain well to the west of Baja California.
Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Barbara continued to weaken as it moved toward Hawaii. At 11:00 a.m. EDT on Saturday the center of Tropical Storm Barbara was located at latitude 18.7°N and longitude 139.2°W which put it about 1040 miles (1670 km) east of Hilo, Hawaii. Barbara was moving toward the west at 17 m.p.h. (28 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 1000 mb.