Tropical Depression Four-E formed south of Acapulco, Mexico on Saturday. At 11:00 p.m. EDT on Saturday the center of Tropical Depression Four-E was located at latitude 14.3°N and longitude 100.0°W which put it about 180 miles (290 km) south of Acapulco. It was moving toward the west-northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1006 mb.
A distinct surface center of circulation developed within a larger area of thunderstorms south of Mexico on Saturday. Showers and thunderstorms began to consolidate near the center. Additional bands of showers and thunderstorms formed outside the core of the circulation. The thunderstorms began to produce upper level divergence which pumped mass away from the core of the depression.
Tropical Depression Four-E will move through an environment favorable for intensification during the next several days. It will move over water where the Sea Surface Temperature is near 30°C. An upper low over the western Gulf of Mexico is enhancing the upper level divergence to the northeast of the tropical depression. An upper level ridge over Mexico is producing easterly winds which are blowing toward the top of the circulation, but the vertical wind shear is minimal. Tropical Depression Four-E could intensify in a tropical storm on Sunday. It has a chance to become a hurricane early next week before it reaches cooler water south of Baja California.
A subtropical ridge over Mexico is steering Tropical Depression Four-E toward the west-northwest and that general motion is expected to continue for another two or three days. On its anticipated track the center of Tropical Depression Four-E is expected to remain south of the coast of Mexico. Rainbands in the northern portion of the circulation could produce locally heavy rain over parts of southern Mexico. The greatest risk would be for flash floods in those areas.