Subtropical Storm Ernesto Forms West of the Azores

Subtropical Storm Ernesto formed west of the Azores on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Subtropical Storm Ernesto was located at latitude 38.1°N and longitude 46.0°W which put it about 695 miles (1120 km) southeast of Cape Race, Newfoundland.  Ernesto was moving toward the north at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1008 mb.

More thunderstorms formed closer to the center of a low pressure system west of the Azores on Wednesday morning and the National Hurricane Center designated the system as Subtropical Storm Ernesto.  Several bands of showers and thunderstorms wrapped around the eastern and northern portions of the circulation.  Bands northwest of the center of Ernesto consisted primarily of showers and lower clouds.  The circulation may have been transporting some cooler, drier, more stable air into that part of the circulation.  Showers and thunderstorms around the center of Ernesto were generating upper level divergence which was pumping mass away to the northeast of the subtropical storm.

Subtropical Storm Ernesto will move through an environment that could support some intensification during the next day or so.  Ernesto will move over water where the Sea Surface Temperature is near 26°C.  It will move through a region where the upper level winds are not too strong and there will not be much vertical wind shear.  Subtropical Storm Ernesto could strengthen during the next 12 to 24 hours.  Ernesto will move over cooler water later on Thursday and it will start to weaken.  An upper level trough east of the U.S. will approach Subtropical Storm Ernesto from the west.  Southwesterly winds ahead of the trough will cause more vertical wind shear and Ernesto could make a transition to an extratropical cyclone.

The southwesterly winds ahead of the upper level trough will steer Subtropical Storm Ernesto in a general northeasterly direction.  On its anticipated track Subtropical Ernesto will pass between the Azores and Greenland.