Former Tropical Depression Sixteen strengthened to Tropical Storm Peter on Sunday morning. At 9:00 a.m. EDT on Sunday the center of Tropical Storm Peter was located at latitude 17.6°N and longitude 56.0°W which put it about 470 miles (755 km) east of the Northern Leeward Islands. Peter was moving toward the west-northwest at 15 m.p.h. (24 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. (95 km/h). The minimum surface pressure was 1008 mb.
Infrared satellite images and satellite derived scatterometer estimates of surface winds indicated that former Tropical Depression Sixteen had strengthened on Sunday morning and the National Hurricane Center designated the system as Tropical Storm Peter. Early morning visible satellite images revealed that strong vertical wind shear was affecting Tropical Storm Peter. An upper level trough north-northeast of Puerto Rico and an upper level ridge east of the Leeward Islands were interacting to produce strong southwesterly winds that were blowing across Peter’s circulation. The low level center of circulation was clearly visible on those images and it was surrounded by showers and lower clouds. Thunderstorms were occurring in bands on the eastern and northern periphery of the circulation around Tropical Storm Peter. Bands in the western and southern parts of Peter consisted primarily of showers and lower clouds.
Tropical Storm Peter will move through an environment marginally favorable for intensification during the next 24 hours. Peter will move over water where the Sea Surface Temperatures are near 29˚C. However, the upper level trough and the upper level ridge will continue to produce strong vertical wind shear. The strong wind shear will inhibit intensification. Tropical Storm Peter could strengthen a little during the next 24 hours. The upper level winds are forecast to get stronger on Monday. Increased vertical wind shear could cause Peter to weaken back to a tropical depression.
Tropical Storm Peter will move around the southern side of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer the depression toward the west-northwest during the next 48 hours. On its anticipated track Tropical Storm Peter could be northeast of the Northern Leeward Islands by Monday morning.
Elsewhere over the Atlantic Ocean, Tropical Depression Seventeen formed southwest of the Cabo Verde Islands. At 5:00 a.m. EDT on Sunday the center of Tropical Depression Seventeen was located at latitude 11.8°N and longitude 28.21°W which put it about 330 miles (530 km) southwest of the Cabo Verde Islands. The tropical depression was moving toward the north-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were’ wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1007 mb. The tropical depression is forecast to move away from the Cabo Verde Islands and to strengthen to a tropical storm.