Powerful Hurricane Lane Prompts Hurricane Watches for Hawaii

A potential threat from powerful Hurricane Lane prompted the Central Pacific Pacific Hurricane Center to issued Hurricane Watches for parts of Hawaii on Tuesday morning.  Hurricane Watches were issued for Hawaii County and Maui County including the islands of Maui, Lanai, Molokai and Kahoolawe.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Lane was located at latitude 14.1°N and longitude 152.3°W which put it about 620 miles (995 km) southeast of Honolulu, Hawaii.  Lane was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 180 m.p.h. (290 km/h).  The minimum surface pressure was 950 mb.

The circulation of Hurricane Lane is very well organized.  There is a circular eye at the center of circulation and the eye is surrounded by a ring of strong thunderstorms.  The strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Lane.  A NOAA P-3 aircraft encountered strong turbulence during a mission into Lane last night and the aircraft will be examined before it flies again.  Storms around the core of the circulation were generating strong upper level divergence which was pumping mass away from the hurricane.

Hurricane Lane has a large symmetrical circulation.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 240 miles (390 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane was 31.6.  The Hurricane Size Index (HSI) was 13.7 and the Hurricane Wind Intensity Size Index (HWISI) was 45.3.  Those indices indicate that Hurricane Lane was stronger and larger than Hurricane Dennis was when Dennis hit the northern Gulf Coast in 2005.

Hurricane Lane will move through an environment capable of supporting a major hurricane for another 24 to 48 hours.  Lane will move over water where the Sea Surface Temperature is between 27°C and 28°C.  It will move through an environment where the upper level winds are weak during the next 24 hours and there will be little vertical wind shear during that time period.  An upper level trough west of Hawaii will move closer to Hurricane Lane on Wednesday.  Southwesterly winds on the eastern side of the trough will increase the vertical wind shear.  Hurricane Lane is likely to weaken on Wednesday, but it could weaken slowly.

Hurricane Lane is moving around the western end of a subtropical ridge over the Eastern North Pacific Ocean.  The ridge has been steering Lane toward the west.  Hurricane Lane will turn more toward the northwest when it reaches the end of the ridge.  The upper level trough could steer Lane more toward the north on Thursday and Friday.  Guidance from forecast models has been trending toward a track closer to Hawaii and that prompted the issuance of Hurricane Watches for some of the Hawaiian Islands.