Two Tropical Depressions Form Over Eastern Pacific

Two tropical depressions formed over the Eastern North Pacific Ocean on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Depression Seven-E was located at latitude 18.7°N and longitude 130.3°E which put it about 1345 miles (2170 km) west of the southern tip of Baja California.  The depression 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 1008 mb.

At 11:00 a.m. EDT on Monday the center of Tropical Depression Eight-E was located at latitude 13.7°N and longitude 119.8°W which put it about 905 miles (1460 km) southwest of the southern tip of Baja California.  The depression was moving toward the west-southwest 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 1008 mb.

The distribution of thunderstorms around Tropical Depression Seven-E was asymmetrical.  The strongest storms were occurring in bands southwest of the center of circulation.  Bands in other parts of the depression consisted primarily of showers and lower clouds.  The depression was already to moving over water where the Sea Surface Temperature was near 25°C.  It was moving under the southwestern part of an upper level ridge which was producing northeasterly winds.  Those winds were blowing toward the top of the depression and they were causing moderate vertical wind shear.  Cooler water and wind shear were contributing to the asymmetrical distribution of thunderstorms.

Tropical Depression Seven-E is likely to weaken since it will continue to move over cooler water.  The depression will move south of a subtropical high pressure system.  The high will steer the depression toward the west while it weakens.  On its anticipated track the depression will weaken long before it could pose a threat to Hawaii.

The distribution of thunderstorms around Tropical Depression Eight-E is also asymmetrical.  Many of the strongest storms were occurring in bands in the western half of the circulation.  Some thunderstorms began to develop in bands in the eastern half of the depression on Monday morning.  Storms on the western side of the circulation began to generate upper level divergence which pumped mass away from the depression.

Tropical Depression Eight-E will move through an environment favorable for intensification during the next several days.  The depression will move over water where the Sea Surface Temperature is near 29°C.  The upper level ridge over the Eastern North Pacific Ocean will produce northeasterly winds which will blow toward the top of the depression.  Those winds will cause some vertical wind shear, but the shear will have less effect because the depression will be over warmer water.  Tropical Depression Eight-E will strengthen during the next 48 hours and it could intensify into a hurricane.

Tropical Depression Eight-E will move around the southern side of the subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer the depression toward the west during the next few days.  On its anticipated track the depression will move in the general direction of Hawaii.