(HOUSTON) -- A flash flood warning was issued for parts of six counties in Texas that include Houston, and parts of the city remain underwater after a weekend of torrential rain.
The warning was issued by the National Weather Service at 6:14 a.m. local time and was expected to last for three hours.
City officials have confirmed Wednesday that another body was discovered near a vehicle after water pumps were brought in to drain a portion of a highway. This death marks the sixth storm-related death in Houston since last week. The statewide death toll blamed on the weather has now reached 16 people.
More rain is the last thing the region needs. In addition to the flash flood threat from rain, a dam southwest of Dallas appears on the brink of breaking.
Photos from the most-affected areas show muddy, brown water filling the streets, with the tops of cars visible in some of the most-flooded roadways.
Drivers stuck in rainwater accounted for at least two of the three deaths that Houston Mayor Annise Parker confirmed on Tuesday following a rain storm Monday night into Tuesday morning. She did not identify the victims but said one person was found inside their vehicle and another was outside and appeared to have suffered a heart attack while trying to push a car out of the flooding.
One of the grimmest discoveries came on Tuesday morning when a biker found a casket on a roadway in southwest Houston.
Walter Rubio told ABC News affiliate KTRK that he saw the casket just laying in the middle of a street, and police opened it and found a dead body inside.
Investigators believe the casket was unearthed from a nearby cemetery during the flooding and determined that it was used to bury a woman who died in 2007. Police have not yet identified the body inside the casket.
Officials have urged residents to avoid touching any objects in the water and to report debris that they find.
Wednesday's rain has already led to partial closures of I-45 because of flooding.
On Tuesday, Texas Gov. Greg Abbott added eight counties to the list of 13 that he had already declared disaster areas.
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