Tag Archives: Hurricane Gaston

Large Hurricane Gaston Prompts Tropical Storm Watch for Azores

Large Hurricane Gaston starting moving more quickly toward the northeast on Wednesday and it prompted a Tropical Storm Watch for some of the Azores.  The Tropical Storm Watch includes Flores, Corvo, Faial, Pico Gracsiosa, Sao Jorge and Terceira in the Azores.

At 8:00 p.m. EDT on Wednesday the center of Hurricane Gaston was located at latitude 35.6°N and longitude 46.5°W which put it about 1000 miles (1610 km) west of Faial in the Azores.  Gaston was  moving toward the northeast at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 969 mb.

Hurricane Gaston has a large circular eye with a diameter of 35 miles (55 km).  The eye is surrounded by a nearly complete eyewall, although the eyewall is thinner in the southwestern quadrant.  Winds to hurricane force extend out about 45 miles (70 km) from the center.  Hurricane Gaston has characteristics of an annular hurricane and the surrounding rainbands are mainly comprised of showers and shallow clouds.  The upper level divergence is inhibited over the southwestern past of the circulation, but divergence is still occurring north and east of the center.

Hurricane Gaston will be moving through an environment that will become increasingly unfavorable.  It is currently over water where the Sea Surface Temperature (SST) is near 27.5°C, but it will be moving over cooler SST during the next few days.  An upper level trough is producing southwesterly winds which are causing vertical wind shear.  The strength of the upper level winds is expected to increase.  The combination of cooler SSTs and more wind shear will weaken Gaston during the next few days.

Hurricane Gaston is being steering toward the northeast by the westerly flow in the middle latitudes.  That general motion is expected to continue.  On its anticipated track Hurricane Gaston could reach the western Azores within 48 hours.  It is expected to weaken below hurricane intensity by that time.  Because of its large size, Gaston could bring wind and rain to many of the Azores.

Gaston Regains Hurricane Intensity East of Bermuda

Gaston intensified back into a hurricane east if Bermuda on Saturday.  At 11:00 p.m. EDT on Saturday the center of Hurricane Gaston was located at latitude 29.6°N and longitude 54.2°W which put it about 655 miles (1055) km east-southeast of Bermuda.  Gaston was moving toward the northwest at 8 m.p.h. (13 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 980 mb.

The circulation of Hurricane Gaston is as well organized as it has ever been.  Gaston has a well formed circular eye surrounded by a ring of thunderstorms.  Multiple spiral rainbands are rotating around the circulation.  Upper level outflow channels to the southwest and east are enhancing upper level divergence and allowing the surface pressure to decrease.

Hurricane Gaston has moved into an environment that is favorable for further intensification.  If it moving over water where the Sea Surface Temperature is near 29°C.  An upper level low northeast of Puerto Rico and an upper level low southeast of Gaston are partially responsible for the two upper level outflow channels.  The upper level winds are weaker in between the two upper level lows and the vertical shear is less than it has been in recent days.  Gaston is likely to intensify further and it could become the first Major Hurricane of the 2016 Atlantic hurricane season.

The steering currents between the two upper lows are weaker and Hurricane Gaston has been moving more slowly toward the northwest.  Gaston is expected to move slowly northward for another day or two.  An upper level trough is likely to begin to steer the hurricane toward the east in 48 to 72 hours.  On its anticipated track Hurricane Gaston should pass well to the east of Bermuda.