A tropical depression redeveloped southeast of Texas from the remnants of former Tropical Storm Harvey on Wednesday morning. The National Hurricane Center (NHC) began issuing advisories on Tropical Depression Harvey again. At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Harvey was located at latitude 21.5°N and longitude 92.5°W which put it about 535 miles (860 km) southeast of Port O’Connor, Texas. Harvey was moving toward the northwest at 9 m.p.h. The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1006 mb.
A Hurricane Watch was issued for the portion of the coast from Port Mansfield to San Luis Pass, Texas. A Tropical Storm Watch was issued for the portion of the coast from the mouth of the Rio Grande River to Port Mansfield and from San Luis Pass to High Island, Texas. NHC also issued a Storm Surge Watch for the portion of the coast from Port Mansfield to High Island.
A reconnaissance aircraft found that a distinct low level center had formed in the remnants of Tropical Storm Harvey on Wednesday morning. The circulation in Tropical Depression Harvey was still in the process of organizing. Stronger thunderstorms were forming near the center of circulation. Additional bands of showers and thunderstorms were forming outside the core of the circulation. The distribution of showers and thunderstorms was somewhat asymmetrical. There were more showers and thunderstorms in the eastern half of the circulation. Although there were fewer showers and thunderstorms in the western half of the circulation, more storms were developing in that part of Tropical Depression Harvey. The thunderstorms near the core were beginning to generate upper level divergence which was pumping away mass to the northeast of the tropical depression.
Tropical Depression Harvey will move through an environment that will become increasing favorable for intensification. Harvey will move over water where the Sea Surface Temperature is near 30°C. An upper level low near the coast of Louisiana is causing some vertical wind shear. However, the low is forecast to move north and weaken and the shear is forecast to decrease. Tropical Depression Harvey may strengthen slowly at first while the circulation is organizing. The rate of intensification will likely increase on Thursday and there could be a period of rapid intensification when the Harvey near hurricane intensity.
Tropical Depression Harvey is moving around the western end of a subtropical high pressure system which is steering Harvey toward the northwest. Harvey is forecast to continue to move toward the northwest and it will approach Texas in about 48 hours. The winds are the steering level are forecast to weaken when Harvey approaches Texas and it could move more slowly as it nears the coast.
Tropical Depression Harvey could evolve into a very dangerous storm. The coast along the western Gulf of Mexico is very susceptible to storm surges. An intensifying, slow moving hurricane could generate dangerous storm surges along the coast. If Harvey stalls after it moves inland, it could drop very heavy rain and there is also the potential for dangerous fresh water flooding.