Tropical Depression Four-E Forms Southwest of Baja California

Tropical Depression Four-E formed just southwest of Baja California on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Depression Four-E was located at latitude 20.5°N and longitude 112.6°W which put it about 240 miles (385 km) southwest of the southern tip of Baja California.  The depression was moving toward the northwest at 7 m.p.h. (11 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 1004 mb.

The circulation around a low pressure system southwest of Baja California exhibited more organization on Monday night and the National Hurricane Center designated the system as Tropical Depression Four-E.  The distribution of thunderstorms around the depression was asymmetrical.  A band of stronger thunderstorms wrapped around the northern side of the center of circulation.  The strongest winds were occurring in that band of storms.  Bands in other parts of the depression consisted of primarily of showers and lower clouds.

Tropical Depression Four-E will move into an environment mostly unfavorable for intensification.  The depression will move over water where the Sea Surface Temperature is near 24.5°C.  An upper level trough over the western U.S. and an upper level ridge over Mexico will produce southwesterly winds which will blow toward the top of the depression.  Those winds will cause moderate vertical wind shear.  The colder water and moderate shear will prevent the potential for significant intensification.  The depression could maintain its intensity during the next six to twelve hours but it is likely to weaken later on Tuesday.

Tropical Depression Four-E will move around the western end of a ridge of high pressure over Mexico.  The ridge will steer the depression slowly toward the northwest.   On its anticipated track Tropical Depression Four-E will pass west of Baja California.