Hurricane Norman rapidly intensified to Category 4 on the Saffir-Simpson Scale on Thursday. At 5:00 p.m. EDT on Thursday the center of Hurricane Norman was located at latitude 17.5°N and longitude 118.8°W which put it about 685 miles (1105 km) west-southwest of the southern tip of Baja California. Norman was moving toward the west at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 175 m.p.h. (285 km/h). The minimum surface pressure was 937 mb.
The circulation Hurricane Norman is very symmetrical. There is a small eye at the center of circulation and the eye is surrounded by a ring of strong thunderstorms. The strongest winds are occurring in that ring of storms. Several bands of showers and thunderstorms were revolving around the core of Hurricane Storm. Storms near the core were generating strong upper level divergence which was pumping mass away from the hurricane in all directions.
Hurricane Norman has a small circulation. Winds to hurricane force extend out about 25 miles (40 km) from the center of circulation. Winds to tropical storm force only extend out about 80 miles (130 km) from the center. The Hurricane Intensity Index (HII) for Norman is 31.6. The Hurricane Size Index (HSI) is 8.6 and the Hurricane Wind Intensity Size Index (HWISI) is 40.2. Hurricane Norman is a small, but powerful hurricane.
Hurricane Norman will remain in a very favorable environment for another day or so. Norman will move over water where the Sea Surface Temperature is near 28°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Norman could strengthen a little more during the next 24 hours unless an eyewall replacement cycle begins. Norman is likely to move over slightly cooler water during the weekend and there may not be enough energy to maintain such a powerful hurricane.
Hurricane Norman will move south of a subtropical ridge over the Eastern North Pacific Ocean. The ridge will steer Norman a little to the south of a due westerly course. On its anticipated track Hurricane Norman will move toward the Central Pacific.
Elsewhere over the Central Pacific Ocean, Hurricane Miriam turned toward the north-northwest. At 5:00 p.m. EDT on Thursday the center of Hurricane Miriam was located at latitude 15.7°N and longitude 141.6°W which put it about 930 miles (1495 km) east-southeast of Hilo, Hawaii. Miriam was moving toward the north-northwest at 8 m.p.h. (13 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 982 mb.