One of the two systems that forecasters have been closely watching in the Atlantic Ocean Basin became the fifth tropical depression at 7:30 p.m. EDT on August 10 in the northeastern Gulf of Mexico. NASA's TRMM satellite confirmed better organization in the system's rainbands just before it was classified as a tropical depression.
System 94L is now Tropical Depression 5 (TD5), and is forecast to strengthen into Tropical Storm Danielle in the next day or so.
The Tropical Rainfall Measuring Mission (TRMM) satellite passed above TD5 on August 10 at 2226 UTC (6:22 p.m. EDT). The rainfall pattern was analyzed using data from TRMM's Precipitation Radar (PR) and TRMM Microwave Imager (TMI) instrument data. The precipitation pattern showed that TD5 was slightly better organized than earlier, helping forecasters with the decision to classify the system as a tropical depression. TRMM is a joint mission between NASA and the Japanese Space Agency, JAXA.
The National Hurricane Center issued a tropical storm warning from Destin, Florida to Intracoastal City Louisiana, including Lake Pontchartrain and New Orleans. That means tropical storm conditions are expected within the warning area in 36 hours. Heavy rain, tropical storm force winds and a storm surge between 2 and 4 feet near landfall and east of landfall are forecast.
At 5 a.m. EDT on August 11, Tropical Depression 5 (TD5) had maximum sustained winds near 35 mph, and slow strengthening is expected. It was centered near 26.8 north latitude and 85.1 west longitude. Estimated minimum central pressure is 1008 millibars. It is expected to continue moving northwest near 10 mph today, and slow on Thursday, August 12 when it will be approaching the north central Gulf of Mexico in the morning.