The primary risk is life-threatening flash flooding, particularly in urban and low-lying areas. Communities from Houston to Galveston and across Louisiana and Mississippi are at heightened risk. The timing of the heaviest rainfall coincides with peak commuting hours, increasing the danger for travelers. Flooded streets and underpasses could trap vehicles, while rapid water accumulation poses a threat to homes and businesses. Emergency officials emphasize that even unnamed systems can bring devastating impacts, underscoring the need for preparedness.