TD 21E Intensifies into Tropical Storm Rick

The organization of Tropical Depression 21E improved slightly on Thursday and the National Hurricane Center upgraded it to Tropical Storm Rick.  At 10:00 p.m. EST on Thursday the center of Tropical Storm Rick was located at latitude 15.2°N and longitude 108.1°W which put it about 365 miles (585 km) southwest of Manzanillo, Mexico.  Rick was moving toward the west-northwest at 10 m.p.h. (16 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 1002 mb.

More thunderstorms formed near the center of Tropical Depression 21E for a few hours on Thursday and the improved organization prompted the National Hurricane Center to upgrade the system to Tropical Storm Rick.  The organization of Rick has diminished in recent hours. The stronger thunderstorms are located northwest of the center of circulation and there are few thunderstorms in the rest of the Rick.  An upper level ridge located east of the tropical storm is producing southerly winds over the top of Rick.  The vertical wind shear is causing the stronger thunderstorms to be northwest of the center.

Rick is over water where the Sea Surface Temperature is near 29°C.  So, there is enough energy in the ocean to support intensification.  However, the strong vertical wind shear is likely to limit intensification and it could weaken Rick if it the shear gets stronger.

The ridge east of Rick is expected to strengthen and to continue to steer the tropical storm toward the west-northwest for another day or two.  After that time Rick will reach the western end of the ridge, and the tropical storm will turn more toward the north.