To put Houston’s flooding in perspective, Tropical Storm Harvey is expected to drop as much rain as Baltimore gets in a year — enough to fill the Chesapeake Bay.
National Weather Service meteorologists predict rainfall in some parts of southeast Texas will surpass 50 inches. They said Tuesday afternoon that one rain gauge southeast of Houston was reporting 49.32 inches, a record for a tropical system in the contiguous 48 states.
That is more than the precipitation reported at Baltimore-Washington International Thurgood Marshall Airport in three of the past five years. Average annual rainfall at BWI, Baltimore’s point of record, is about 46 inches.
A widespread 25 inches has fallen across Greater Houston. Baltimore has never seen nearly as much rainfall within a month.
About 18 inches of rain fell in Baltimore’s wettest month on record, in August 1955, when Hurricane Connie hit.
The volume of all the rainfall flooding the Houston region is estimated to approach 20 trillion gallons, once Harvey finally dissipates and departs.
That could mean a deluge on par with the normal volume of the Chesapeake Bay — about 18 trillion gallons.