An area of low pressure organized on Wednesday well east-southeast of Hawaii and it has been classified as Tropical Storm Guillermo. At 5:00 a.m. EDT on Thursday the center of Tropical Storm Guillermo was located at latitude 8.5°N and longitude 126.3°W which put it about 2070 miles (3340 km) east-southeast of Hilo, Hawaii and about 1475 miles (2370 km) southwest of the southern tip of Baja California. Guillermo was moving toward the northwest at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1003 mb.
Guillermo formed at an unusually low latitude over the eastern North Pacific. It is over an area where the Sea Surface Temperatures (SSTs) are near 29°C. The upper level winds are light over the circulation and there is not much vertical wind shear. Guillermo will be moving through an environment favorable for intensification during the next two or three days and a period of rapid intensification will be possible when it nears hurricane intensity. Guillermo will move over cooler SSTs when it gets closer to Hawaii and the wind shear may also increase.
A subtropical ridge north of Guillermo is steering the tropical storm toward the northwest and the ridge is expected to continue to steer the tropical storm toward the west-northwest during the next 48 to 72 hours. Later in the weekend an upper level trough approaching from the west could turn Guillermo more toward the northwest.