Tropical Storm Alberto Strengthens Near Mexico

Tropical Storm Alberto strengthened on Wednesday evening as it neared the coast of Mexico.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Alberto was located at latitude 21.5°N and longitude 95.9°W which put it about 135 miles (220 km) east-southeast of Tampico, Mexico and about 320 miles (510 km) south-southeast of Brownsville, Texas.  Alberto was moving toward the west at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 993 mb.

Tropical Storm Alberto was getting stronger on Wednesday evening as it approached the coast of Mexico near Tampico.  Thunderstorms near the center of Alberto’s circulation rose higher into the atmosphere.  A band of thunderstorms wrapped around the southern and eastern side of the center of circulation.  Other bands of showers and thunderstorms were revolving around the center of Tropical Storm Alberto.  Storms near the center of Alberto generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

The distribution of winds in Tropical Storm Alberto was still asymmetrical.  The circulation around the northern side of Alberto’s circulation was interacting with the southern part of a strong high pressure system over the eastern U.S.  The interaction of the two pressure systems was causing a large area of tropical storm force winds in the northern side of Tropical Storm Alberto.  Winds to tropical storm force extended out 460 miles (740 km) in the northern side of Alberto’s circulation.  Winds to tropical storm force only extended out 60 miles (95 km) in the southern half of Alberto.

Tropical Storm Alberto will move through an environment favorable for intensification during the next few hours.  Alberto will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the the center of an upper level ridge over the western Gulf of Mexico.  The upper level winds are weak near the center of the ridge and there will be little vertical wind shear.  Tropical Storm Alberto is likely to intensify during the next few hours until the center makes landfall on the coast of Mexico.

Tropical Storm Alberto will move around the southern side of a strong high pressure system over the eastern U.S.  The high pressure system will steer Alberto toward the west during the next 24 hours.  On its anticipated track, Tropical Storm Alberto will make landfall on the coast of northern Mexico early on Thursday.  The center of Alberto will make landfall a little south of Tampico, Mexico.