Tropical Storm Iselle was spinning southwest of Baja California on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Iselle was located at latitude 20.1°N and longitude 118.6°W which put the center about 590 miles (950 km) west-southwest of the southern tip of Baja California.  Iselle was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 988 mb.

Tropical Storm Iselle strengthened on Monday.  More thunderstorms developed near the center of Iselle’s circulation.  Bands of showers and thunderstorms were also revolving around the center of Tropical Storm Iselle.  Storms near the center of Iselle generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

Wind to tropical storm force extended out 195 miles (315 km) from the center of Tropical Storm Iselle.

Tropical Storm Iselle will move through an environment that will become unfavorable for intensification during the next 24 hours.  Iselle will move over water where the Sea Surface Temperatures are near 27°C.  It will move under the southern part of an upper level trough that is west of the West Coast of the U.S  The upper level trough will produce southwesterly winds that will blow toward the top of Iselle’s circulation.  Those winds will cause the vertical wind shear to increase on Tuesday.  In addition, Iselle will move into a mass of drier air that is west of Baja California.  Tropical Storm Iselle is likely to start to weaken on Tuesday because of the effects of the increased vertical wind shear and the drier air.

Tropical Storm Iselle will move around the southwestern part of a high pressure system that is over the Eastern North Pacific Ocean.  The high pressure system will steer Iselle toward the west-northwest during the next 24 hours.  On its anticipate track, Tropical Storm Iselle will move farther away from Baja California.

Elsewhere, former Tropical Storm Moke weakened to a tropical depression south of Hawaii and Tropical Storm Lala weakened gradually far to the northwest of Hawaii.

At 11:00 p.m. EDT on Monday the center of Tropical Depression Moke was located at latitude 16.0°N and longitude 163.0°W which put the center about 435 miles (695 km) east of Johnston Island.  Moke was moving toward the west at 14 m.p.h. (22 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 1005 mb.

At 11:00 p.m. EDT on Monday the center of Tropical Storm Lala was located at latitude 34.3°N and longitude 175.6°W which put the center about 435 miles (705 km) north-northeast of Kure Atoll.  Lala was moving toward the northwest at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 992 mb.