Former Subtropical Storm Ernesto made a transition to a tropical storm on Thursday afternoon. At 5:00 p.m. EDT on Thursday the center of Tropical Storm Ernesto was located at latitude 43.0°N and longitude 41.0°W which put it about 645 miles (1035 km) east-southeast of Cape Race, Newfoundland. Ernesto was moving toward the northeast at 18 m.p.h. (30 km/h). The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h). The minimum surface pressure was 1007 mb.
Even though now Tropical Storm Ernesto moved over water where the Sea Surface Temperature was between 24°C and 25°C, there was enough energy in the upper ocean to cause more thunderstorms to develop. In addition, many of the thunderstorms developed close to the center of circulation. The inner bands of showers and thunderstorms became stronger and the bands in the outer parts of the circulation weakened. Ernesto exhibited a structure like a tropical cyclone and the National Hurricane Center classified the system as a tropical storm in the 5:00 p.m. EDT advisory.
Tropical Storm Ernesto will move over much cooler water during the next 24 hours. It is likely to make a transition to an extratropical cyclone when it moves over the cooler water. Ernesto could strengthen when colder air is pulled into the western half of the circulation and a cold front forms south of the center. The development of the cold front and upper level divergence could strengthen the pressure gradient force which would give the air a stronger push. An upper level trough east of the U.S. is forecast to steer Ernesto in the general direction of Ireland and the United Kingdom.
Former Hurricane Ophelia brought strong winds to Ireland and parts of the United Kingdom on Monday. Although former Hurricane Ophelia had made a transition to an extratropical cyclone before it reached Ireland, it was still a very powerful storm when it moved across that region. There were reports of several fatalities, damage and power outages across Ireland. Met Eireann (the Irish meteorological agency) reported the following wind gusts during the passage of former Hurricane Ophelia.
At the Fastnet Lighthouse (anemometer at 200 feet [61 meters] ) there was a gust of 191 km/h (118 m.p.h.). Sherkin Island reported a wind gust of 135 km/h (84 m.p.h.) before the power went out. Cork airport reported a wind gust of 126 km/h (78 m.p.h.) before the power went out. Shannon airport reported a wind gust of 122 km/h (76 m.p.h.). Roches Point reported a wind gust of 156 km/h (97 m.p.h.). The Kinsale Platform reported a wind gust of 141 km/h (87 m.p.h.) and the Dublin airport reported a wind gust of 104 km/h (65 km/h).
Hurricane Ophelia strengthened into a Category 3 hurricane on the Saffir-Simpson Scale on Saturday morning as it moved south of the Azores. That made Ophelia a major hurricane. At 11:00 a.m. EDT on Saturday the center of Hurricane Ophelia was located at latitude 34.8°N and longitude 26.6°W which put it about 220 miles (355 km) south of the Azores. Ophelia was moving toward the northeast at 25 m.p.h. (40 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (220 km/h). The minimum surface pressure was 960 mb.
It is very unusual to have such a strong hurricane near the Azores, but Ophelia contains all of the elements of a major hurricane. There is a circular eye at the center of circulation. The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms. Well formed rainbands exists in the outer portions of the circulation. Storms in the core of Ophelia are generating upper level divergence which is pumping mass away to the northeast of the hurricane. Winds to hurricane force extend out about 40 miles (65 km) from the center of circulation. Winds to tropical storm force extend out about 125 miles (205 km) from the center.
Hurricane Ophelia is moving over water where the Sea Surface Temperature is near 25°C. Normally, water at that temperature would be considered to be too cool to support the development of a major hurricane. However, the temperature of the air in the upper troposphere is also cool and so the atmosphere is unstable enough to allow for the development of deep convection. An upper level trough west of Ophelia is producing southwesterly winds which are blowing toward the top of the circulation. There are also southwesterly winds in the lower and middle levels of the atmosphere and so the vertical wind shear is not strong enough to inhibit intensification
Hurricane Ophelia will be moving over cooler water and it is likely to weaken gradually during the next several days. When Ophelia moves over the cooler water it will make a transition to an extratropical cyclone. The size of the circulation will increase during the transition. Hurricane Ophelia will evolve into a large very powerful extratropical cyclone during the next several days.
The trough west of Ophelia is steering the hurricane toward the northeast. Hurricane Ophelia is expected to turn more toward the north during the next two or three days. On its anticipated track Hurricane Ophelia will pass east of the Azores later today. The strong extratropical cyclone that Ophelia will transition into could approach Ireland and the United Kingdom by Monday morning. That cyclone will bring very strong winds and heavy rain to that region.