Tropical Storm Barry Strengthens South of Louisiana

Tropical Storm Barry strengthened south of Louisiana on Friday morning.  Hurricane Hunters flying into Barry found that the maximum sustained wind speed had increased to 65 m.p.h. (105 km/h).  At 11:00 a.m. EDT on Friday the center of Tropical Storm Barry was located at latitude 28.2°N and longitude 90.4°W which put it about 115 miles (185 km) south-southeast of Morgan City, Louisiana.  Barry was moving toward the west-northwest at 5 m.p.h. (8 km/h). The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 998 mb.

A Hurricane Warning is in effect for the portion of the coast from Intracoastal City to Grand Isle, Louisiana. Hurricane Watches have been issued for the portions of the coast from the Mouth of the Mississippi River to Grand Isle, Louisiana and from Intracoastal City to Cameron, Louisiana. Tropical Storm Warnings are in effect for the portions of the coast from the Mouth of the Pearl River to Grand Isle, Louisiana and from Intracoastal City to Cameron, Louisiana. A Tropical Storm Watch has been issued for the portion of the coast from the Mouth of the Pearl River to the Mississippi/Alabama border. A Tropical Storm Warning is in effect for Lake Pontchartrain, Lake Maurepas and New Orleans.

The circulation around Tropical Storm Barry exhibited greater organization on Friday morning.  Thunderstorms developed in a band around the southern side of the center of circulation.  More thunderstorms also formed in bands that stretched around the western, southern and eastern sides of the circulation.  Bands in the northern portion of the circulation consisted primarily of showers and lower clouds, although there were some thunderstorms in the parts of those bands over land.  Winds to tropical storm force extended out about 170 miles (280 km) from the center of circulation.  Storms just south of the center were generating upper level divergence which was pumping mass away to the west of Tropical Storm Barry.  The removal of mass allowed the surface pressure to decrease and it was down to 998 mb on Friday morning.

Tropical Storm Barry will move through an environment that is some what favorable for intensification.  Barry will move south of a narrow upper level ridge that stretches from east Texas to south Alabama.  The ridge will produce northeasterly winds which will cause some vertical wind shear.  The shear is one of the reasons why there are fewer thunderstorms in the northern part of the circulation.  Reconnaissance aircraft reported that the middle level center was a little to the south of the surface center.  The tilt of the circulation with height is also the result of the vertical wind shear.  However, the shear will not be strong enough to prevent intensification.  Tropical Storm Barry will move over water where the Sea Surface Temperature is near 30.5°C.  It will extract a lot of energy from the Gulf of Mexico.  Tropical Storm Barry is forecast to strengthen into a hurricane during the next 24 hours.

Tropical Storm Barry is moving around the southwestern part of a ridge of high pressure over the southeastern U.S.  The ridge will steer Barry slowly toward the west-northwest during the next few hours.  Barry will turn more toward the northwest later on Friday.  On its anticipated track the center of Tropical Storm Barry will approach the coast of Louisiana late Friday night.  Barry is forecast to be a hurricane when it reaches the coast.  The broad circulation will cause mostly minor wind damage over a large area.  There could be widespread power outages.  Barry will also generate a storm surge of 6 to 9 feet (2 to 3 meters near where the center makes landfall.  Tropical Storm Barry will drop heavy rain when it moves slowly inland.  Flooding is a serious risk, since soils are nearly saturated and many creeks and rivers are already high.