Flash Flood — Harris, Texas

2016-04-17 to 2016-04-18 · near Hockley, Harris, Texas

Event narrative

Heavy rain caused extensive flooding especially over western half of the county where 10 to 15 inches of rain fell in less than a 12 hour period. An estimated 40,000 vehicles and 10,000 homes were flooded. Seven people in Harris County drowned in their vehicles when they drove into flooded roadways. There were numerous high water rescues.

Wider weather episode

A slow moving upper low over the Southwestern U.S. combined with near record level moisture aided in producing extremely heavy rainfall and devastating flooding over portions of Harris, Waller and Fort Bend Counties. Northwest to southeast orientated bands of precipitation commenced during the early evening hours of April 17th across extreme southwestern and western Harris County as well as north and west into Grimes, Waller, Fort Bend, Austin and Colorado Counties. Between 8:00 p.m. and 9:00 p.m. thunderstorms began to greatly intensify and slow their northward movement over Waller County and, by late evening, had stalled and began shifting eastward into western Harris County. Excessive rainfall spread across northwestern Harris County during the late evening hours of April 17th and into the early morning hours of April 18th. Slow thunderstorm movement and rain rates over 4 inches per hour resulted in a large portion of northwest Harris and Waller Counties receiving between 10 and 20 inches of rainfall over mainly a 12 hour period. A few CoCoRaHS gauges in Waller County measured over 20 inches.

The flooding resulted in 8 direct fatalities over the region, all drownings in vehicles. Six of these were in Harris County with 1 in Waller County and another in Austin County. An estimated 40000 cars and trucks were flooded. Several bayous and creeks were flooded. The Addicks Barker Reservoir was severely impacted. At least 10,000 homes were flooded. Damage was estimated from Damage Survey Reports to be near $60 million.

View location on OpenStreetMap → (30.0622, -95.8832)

Source: NOAA Storm Events Database, event_id 629833. Narrative written by the NWS forecast office that issued the report.