Hurricane Dora weakened as it moved over cooler water south of Baja California on Tuesday. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Dora was located at latitude 19.6°N and longitude 111.4°W which put it about 245 miles (400 km) south-southwest of the southern tip of Baja California. Dora as moving toward the west-northwest at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 995 mb.
Tropical Storm Dora is moving over water where the Sea Surface Temperature (SST) is near 24°C. The circulation of Tropical Storm Dora is still very well organized but it is unable to extract sufficient energy from the upper ocean to maintain its intensity. As a result, the showers and thunderstorms are not rising as far into the atmosphere and the circulation is spinning down. There is little vertical wind shear and so the circulation is still symmetrical, but it is not as vigorous. The lack of wind shear will cause the weakening to occur more slowly than it would have if the upper level winds were stronger.
A subtropical ridge is steering Tropical Storm Dora toward the west-northwest and that general motion is expected to continue for anther day or two. On its anticipated track, Tropical Storm Dora will move farther away from Baja California. The forecast track would keep Dora over cooler SSTs and it should continue to weaken.
Tropical Storm Dora intensified rapidly into a hurricane during the overnight hours. Dora is the first hurricane to develop over the Eastern North Pacific during 2017. At 11:00 a.m. EDT on Monday the center of Hurricane Dora was located at latitude 17.3°N and longitude 106.3°W which put it about 220 miles (350 km) south of Cabo Corrientes, Mexico. Dora was moving toward the west-northwest at 13 m.p.h. (20 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 985 mb.
The circulation of Hurricane Dora is very well organized. A circular eye exists at the center of circulation. A ring of strong thunderstorms surrounds the eye. Additional bands of showers and thunderstorms are revolving around the core of the circulation. Thunderstorms in Dora are generating well developed upper level divergence which is pumping large quantities of mass out in all directions.
Dora is a small hurricane. Wind to hurricane force extend out about 25 miles (40 km) from the center of circulation. Winds to tropical storm force extend out about 80 miles (130 km) from the center. The Hurricane Intensity Index (HII) is 12.7. The Hurricane Size Index (HSI) is 7.3. The Hurricane Wind Intensity Size Index (HWISI) is 20.0.
Hurricane Dora will move through an environment favorable for intensification for another 12 to 18 hours. It is currently over water where the Sea Surface Temperature (SST) is near 28°C. Dora will move over SSTs that will gradually be cooler, but they should be warm enough to support further intensification for another 12 to 18 hours. Hurricane Dora is moving through an area where upper level winds are weak and there is almost no vertical wind shear. Hurricane Dora is likely to strengthen further during the next few hours. Dora will move over much cooler SSTs when it passes south of Baja California and it will begin to weaken on Tuesday.
A subtropical ridge to the north of Dora is steering the hurricane toward the west-northwest and that general motion is expected to continue for another 24 to 48 hours. On its anticipated track the center of Hurricane Dora will pass south of Baja California.