The National Hurricane Center (NHC) indicated that a low pressure system over the Eastern North Pacific Ocean east-northeast of Hawaii could develop into a subtropical or a tropical cyclone during the next 48 hours. The low pressure system is currently designated as Invest 90E. At 1:00 p.m. EST on Thursday the center of Invest 90E was located at latitude 21.8°N and longitude 136.1°W which put it about 1280 miles (2065 km) east-northeast of Hilo, Hawaii. It was moving toward the west-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1006 mb.
The National Hurricane Center issued a Special Tropical Weather Outlook on Thursday afternoon which indicated that a low pressure system over the Eastern North Pacific Ocean had a 40% probability of development into a subtropical or a tropical cyclone during the next 48 hours. The low pressure system has been moving slowly toward the west between Baja California and Hawaii. The low pressure system currently has a hybrid structure. A well organized low level center of circulation was evident on visible satellite images. The low level center was located just to the east of a low pressure system in the middle and upper troposphere. The upper low was producing southerly winds that were blowing toward the top of the low level circulation. Those winds were causing moderate vertical wind shear and the wind shear was affecting the structure of the system. The strongest thunderstorms were occurring in bands north and east of the low level center of circulation. Bands south and west of the low level center consisted primarily of showers and lower clouds.
Invest 90E will move through an environment somewhat favorable for the formation of a subtropical or a tropical cyclone during the next 24 hours. The surface center of circulation will move over water where the Sea Surface Temperatures are near 24˚C. Since the upper low contains colder air, that water temperature is warm enough to support the development of a subtropical or a tropical cyclone. The low in the middle and upper troposphere will continue to cause moderate vertical wind shear. The wind shear will inhibit the development of a tropical cyclone. The current hybrid structure of Invest 90E and the marginally warm Sea Surface Temperatures would favor the development of a subtropical cyclone. However, if the strength of the upper level winds decreases, then a tropical cyclone could form.
Invest 90E will move south of a surface high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer the low level center of circulation toward the west-northwest during the next 24 hours. On its anticipated track Invest 90E will move slowly toward the Central Pacific Ocean.
