Tropical Storm Dolphin (07W) has been meandering around within a much larger region of low pressure west of the International Dateline, but it is expected to take a turn toward the west on Monday.  At 10:00 p.m. EDT on Sunday the center of Tropical Storm Dolphin was located at latitude 9.3°N and longitude 159.4°E which put it about 180 miles north-northeast of Pohnpei and about 1040 miles east-southeast of Guam.  Dolphin was moving toward the north-northwest at 10 m.p.h.  The maximum sustained wind speed was 45 m.p.h. and there were gusts to 60 m.p.h.  The minimum surface pressure was 993 mb.

An upper level ridge northeast of Dolphin is producing easterly winds over the top of the circulation and is creating moderate vertical wind shear.  The wind shear is contributing to an asymmetrical circulation where most of the thunderstorms are on the western side.  The shear is inhibiting further organization of the circulation and has kept Dolphin as a minimal tropical storm.  Dolphin is over warm Sea Surface Temperatures and it has the potential to intensify if the wind shear decreases.

A subtropical ridge is expected to build north of Dolphin and to steer it mainly toward the west for much of the coming week.  On its expected track Dolphin could approach Guam in about four days.