A tropical wave designated as Potential Tropical Cyclone Four brought rain to northeastern Mexico on Saturday night. At 11:00 p.m. EDT on Saturday the center of Potential Tropical Cyclone Four was located at latitude 25.3°N and longitude 97.9°W which put it about 60 miles (95 km) southwest of the Mouth of the Rio Grande River. Potential Tropical Cyclone Four was moving toward the northwest at 13 m.p.h. (20 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 1010 mb.

A tropical wave designated as Potential Tropical Cyclone Four moved inland over northeastern Mexico during Saturday night. A center of circulation never formed in the lower levels of the of the tropical wave and so it never developed into a tropical depression or a tropical storm. The tropical wave will move northwest over the Lower Rio Grande Valley on Sunday. Thunderstorms in the tropical wave could drop locally heavy rain over northeastern Mexico and South Texas. Some places could receive 3 to 5 inches (75 to 125 mm) of rain. The heavy rain could cause flash floods in some locations.