Tropical Storm Warnings Issued for South Texas and Northern Mexico

Tropical Storm Warnings were issued for the coast of south Texas and northern Mexico early on Tuesday. A low pressure system over the southern Gulf of Mexico was designated as Potential Tropical Cyclone One. At 8:00 a.m. EDT on Tuesday the center of Potential Tropical Cyclone One was located at latitude 21.5°N and longitude 92.8°W which put it about 355 miles (575 km) east-southeast of La Pesca, Mexico and about 420 miles (680 km) southeast of Brownsville, Texas. The low pressure system was moving toward the north at 6 m.p.h. (10 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 999 mb.

A large low pressure system was over the southern Gulf of Mexico on Tuesday morning. The low pressure system did not exhibit the usual structural features of a tropical cyclone. So, the U.S. National Hurricane Center continued to designate the system as Potential Tropical Cyclone One.

The large low pressure system still did not have a well defined, distinct low level center of circulation. There were few thunderstorms in the broad region around the middle of the low pressure system. The surface winds were relatively weak near the middle of the low pressure system. The strongest winds were occurring in a band of thunderstorms about 285 miles (460 km) north of the middle of Potential Tropical Cyclone One. Some winds in that area were blowing at tropical storm force. Elsewhere in the low pressure system, the winds were blowing at less than tropical storm force.

The low pressure system will move through an environment favorable for the development of a tropical cyclone during the next 24 hours. Potential Tropical Cyclone One will move over water where the Sea Surface Temperatures are near 30°C. It will move under the the center of an upper level ridge centered near the Yucatan Peninsula. The upper level winds are weak near the center of the ridge and there will be little vertical wind shear. Potential Tropical Cyclone One could develop into a tropical storm during the next 24 hours. In order to be classified as a tropical cyclone, a distinct low level center of circulation would have to form. Thunderstorms would have to develop and to persist near the low level center. The strongest winds would need to occur near the low level center of circulation in order for Potential Tropical Cyclone One to be classified as a tropical storm.

Potential Tropical Cyclone One will move around the northern part of a large counterclockwise circulation called a Central American Gyre (CAG) during the next 12 hours. The Central American Gyre will steer the low pressure system toward the north-northwest on Tuesday. A strong high pressure system over the eastern U.S. will block Potential Tropical Cyclone One from moving toward the north on Wednesday. The high pressure system will turn the low pressure system toward the west-northwest. On its anticipated track, Potential Tropical Cyclone One could approach the coast of northern Mexico or southern Texas on Wednesday evening.