Tag Archives: Pacific Northwest

Oho Becomes a Hurricane Southeast of Hawaii

The circulation around Tropical Storm Oho became much more organized on Tuesday and it intensified into a hurricane.  At 5:00 p.m. EDT on Tuesday the center of Hurricane Oho was located at latitude 16.6°N and longitude 150.2°W which put it about 385 miles (620 km) east-southeast of Hilo, Hawaii.  Oho was moving toward the northeast at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 85 m.p.h. (140 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 975 mb.

A primary rainband wrapped tightly around the center of circulation and created a banded eye feature.  In addition other rainbands developed around the core of the circulation and Oho looks much more like a tropical cyclone today.  Thunderstorms near the center of circulation are generating upper level divergence, especially northeast of the center.  The upper level divergence caused the surface pressure to decrease and the wind speeds to increase.

Hurricane Oho is moving over water where the Sea Surface Temperature (SST) is near 28°C.  The upper level winds are currently fairly light and there is not much vertical wind shear.  The conditions are favorable for intensification and Oho could get stronger during the next 24 hours.  After that time Oho will move over cooler SSTs and the vertical wind shear will increase.  Oho should start to weaken and begin a transition to an an extratropical cyclone.

A large upper level trough north of Hawaii will steer Hurricane Oho toward the northeast during the next few days.  On its anticipated track Oho will pass about 400 miles east of Hawaii.  The extratropical stage of Hurricane Oho could approach the Pacific Northwest in three or four days.