Tropical Storm Watches were issued for parts of the coast of south Texas and northern Mexico on Monday afternoon. A low pressure system over the Bay of Campeche was designated as Potential Tropical Cyclone One. At 5:00 p.m. EDT on Monday the center of Potential Tropical Cyclone One was located at latitude 20.3°N and longitude 93.2°W which put it about 380 miles (615 km) southeast of La Pesca, Mexico and about 470 miles (755 km) southeast of Brownsville, Texas. The low pressure system was moving toward the north-northwest at 7 m.p.h. (11 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 1001 mb.
A Tropical Storm Watch was in effect for the portion of the coast from Port O’Connor, Texas to Boca de Catan, Mexico.
A large low pressure system formed over the Bay of Campeche on Monday. The low pressure system did not exhibit the usual structural features of a tropical cyclone. So, the U.S. National Hurricane Center designated the system as Potential Tropical Cyclone One. Since the low pressure system has the potential to develop into a tropical storm, Tropical Storm Watches were issued for the coast of southern Texas and northern Mexico.
The large low pressure system 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) northeast 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. 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 northeastern part of a large counterclockwise circulation call a Central American Gyre (CAG). The Central American Gyre will steer the low pressure system toward the north-northwest during the next 24 hours. A strong high pressure system over the eastern U.S. will turn the low pressure system toward the west-northwest on Wednesday. On its anticipated track, Potential Tropical Cyclone One could approach the coast of northern Mexico or southern Texas on Wednesday evening.
Potential Tropical Cyclone One could be a tropical storm when it approaches the coast. That is the reason the Tropical Storm Watches were issued. Even if Potential Tropical Cyclone One does not develop into a tropical storm, it will drop heavy rain on parts of northern Mexico and southern Texas. The low pressure system could also cause a storm surge of up to four feet (one meter) where the winds blow the water toward the coast.