Fernanda Rapidly Intensifies Into a Hurricane

Former Tropical Storm Fernanda rapidly intensified into a hurricane on Thursday.  At 5:00 p.m. EDT on Thursday the center of Hurricane Fernanda was located at latitude 11.2°N and longitude 116.0°W which put it about 900 miles (1450 km) south-southwest of the southern tip of Baja California.  Fernanda was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (155 km/h).  The minimum surface pressure was 990 mb.

A primary rainband wrapped around the center of circulation and an eye appeared intermittently on visible satellite images on Thursday afternoon.  The improved organization of the inner core of Fernanda allowed it to intensify rapidly into a hurricane.  The distribution of thunderstorms become more symmetrical and circulation exhibited a more circular appearance.  Thunderstorms in the inner core began to generate strong upper level divergence which pumped out mass in all directions.  The divergence of mass allowed the surface pressure to decrease and the wind speeds to increase rapidly.

Hurricane Fernanda will move through an environment that will be favorable for further intensification during the next two days.  Fernanda will move over water where the Sea Surface Temperature (SST) is near 29°C.  An upper level ridge northeast of Fernanda is producing easterly winds which are blowing toward the top of the hurricane.  However, the speed of the upper level winds decreased on Thursday and there is less vertical wind shear.  A combination of a well organized inner core, warm SSTs and reduced vertical wind shear resulted in rapid intensification of Fernanda into a hurricane.  Rapid intensification could continue for another 24 to 36 hours and Fernanda is forecast to become a major hurricane on Friday.

A subtropical ridge to the north of Fernanda is steering the hurricane toward the west and a general westerly motion is expected to continue for several more days.  On its anticipated track Hurricane Fernanda will move farther away from Mexico.