Hurricane Tammy moved north of the Leeward Islands on Sunday. At 11:00 p.m. EDT on Sunday the center of Hurricane Tammy was located at latitude 20.8°N and longitude 64.0°W which put it about 190 miles (305 km) north-northwest of Anguilla. Tammy was moving toward the northwest at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 993 mb.

Hurricane Tammy maintained its intensity on Sunday as it moved north of the Leeward Islands, but Tammy was looking a little weaker on Sunday evening. An upper level trough near the east coast of the U.S. was producing strong southwesterly winds that were blowing toward the top of Tammy’s circulation. Those winds were causing strong vertical wind shear. In addition, some drier air appeared to be entering the southwestern part of Hurricane Tammy.

The effects of the strong wind shear and the drier air caused the distribution of thunderstorms in Hurricane Tammy to become asymmetrical again. Many of the thunderstorms were occurring in bands in the northern and eastern parts of Tammy’s circulation. Bands in the western and southern parts of the circulation consisted primarily of showers and lower clouds. Winds to hurricane force extended out 25 miles (40 km) from the center of Hurricane Tammy. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation.

Hurricane Tammy will move through an environment that will be unfavorable for intensification during the next 24 hours. Tammy will move over water where the Sea Surface Temperatures are near 29°C. However, the upper level trough near the east coast of the U.S. will continue to cause strong vertical wind shear. The strong wind shear will inhibit intensification and Hurricane Tammy could weaken on Monday.

Hurricane Tammy will move around the western end of a subtropical high pressure system over the Atlantic Ocean. The high pressure system will steer Tammy toward the north during the next 24 hours. On its anticipated track, Hurricane Tammy will move farther north of the Leeward Islands on Monday.