The disturbance was located a little more than 100 miles south of Louisiana early Monday and was showing signs of organization. The National Hurricane Center gives it a 70% chance of becoming a tropical depression or tropical storm before reaching the coast Tuesday.
If it strengthens into a named storm, it would be called Edouard. Tropical storm watches or warnings could be issued for portions of the upper Texas Gulf Coast later Monday.
A weather reconnaissance aircraft Monday morning is set to investigate the system and should provide a clearer picture of its strength and track. Current forecasts generally bring the disturbance toward the upper Texas or southwestern Louisiana coasts Tuesday, but small changes in its path could significantly affect local rainfall totals.
Even after the recent dry stretch, flooding remains a concern. Downpours falling at rates of 2 to 4 inches per hour could quickly overwhelm streets and drainage systems, especially where the heaviest rain bands stall.
Rainfall: Rainfall totals of 1 to 3 inches are expected generally east and southeast of a line from Huntsville to Galveston. Some locations could receive 5 to 7 inches in a worst-case scenario if the disturbance slows down or its heaviest rain bands repeatedly move over the same areas.
The heaviest rainfall is expected near and east of Interstate 45, although the exact location will depend on the track. Localized street flooding could develop, particularly where several inches of rain fall in a short time.
Wind: Tropical storm-force wind gusts of 40 to 50 mph could affect the eastern upper Texas Gulf Coast, coastal waters and Chambers County from late Tuesday morning through Tuesday evening. Gusty winds could cause isolated power outages, especially near where the disturbance moves ashore, but widespread outages are not expected.
Widespread coastal flooding is not expected, but elevated waves could affect areas near where the center moves ashore.
Rain chances could increase Monday night, mainly east and southeast of Galveston. The greatest risk for heavy rain and localized flooding will come Tuesday into Wednesday as the system approaches the coast and moves inland.
A track farther east toward southwestern Louisiana would likely mean lower rainfall totals west of Interstate 45, while a track closer to Houston would increase the flood threat across the metro area.
Even without becoming Edouard, the disturbance could turn Houston’s long dry spell into a dangerous flooding threat by midweek.