Wednesday, August 30, 2017

Tropical Storm Harvey River Flooding Shatters Records and Could Last For Days

Jon Erdman
Published: August 30,2017

Tropical Storm Harvey's torrential rain has already pushed rivers and bayous to record levels in some locations, and rivers in parts of Texas and Louisiana may take days, if not weeks, to return within their banks.
(FULL COVERAGE ON HARVEY: Hurricane Central)
Record flooding has already been recorded at 17 different National Weather Service river forecast locations where the period extends to at least before 2000. Another two locations may set new record crests in the days ahead.
Parts of southeast Texas had received more than 40 inches of rain, with at least one location – Cedar Bayou gauge near Highlands, Texas – setting a new continental U.S. rainfall record for any tropical cyclone with 51.88 inches as of 3 p.m. CDT Tuesday.
Radar-estimated storm-total rainfall from Harvey through late Wednesday morning, Aug. 30.
The National Weather Service is forecasting major river flooding in dozens of locations in southeast Texas and southwest Louisiana.
(MORE: NWS River Flood Forecasts)
Rivers forecast to be above flood stage by the National Weather Service River Forecast Centers, as of Wednesday, Aug. 30. Locations in major flood are denoted by purple dots, moderate flood by red dots and minor flood by orange dots.
(MORE: How You Can Help Victims)
Here is a rundown of notable current and forecast statuses of rivers and bayous, generally those in major flood, according to the National Weather Service. Locations in bold indicate those that have already set new record crests. Click on each link for the latest National Weather Service river stage forecast.

Near Houston Metro

Cypress Creek (northern Harris County):
  • Near Westfield: Already topped previous record from Oct. 8, 1949; should fall below flood stage by the Labor Day weekend
  • Near CypressAlready topped previous record from Oct. 18, 1994; should fall below flood stage by the Labor Day weekend
  • Near Hockley: Crested at fourth-highest level, highest since Oct. 1998 flood; should fall below flood stage by the Labor Day weekend
Meteorologist Jeff Lindner at the Harris County Flood Control District noted the creek at Interstate 45 was almost 5 feet higher than it was during Allison in 2001, and water neared the second story of an apartment building at Grant Road Monday morning.
San Jacinto River:
Buffalo Bayou:
  • At West Belt DriveAlready topped previous record from Aug. 18, 1983; may remain in record flood into next week due to nearby earthen levee release
  • At Piney Point VillageAlready topped previous record from Mar. 4, 1992; may remain in record flood into next week
  • At Shepherd Drive: Crested initially at highest level since Allison 2001
Trinity River:
  • Near Goodrich: Crested at third-highest level on record, highest since Oct. 18, 1994; many homes below Lake Livingston flooded; forecast to be in major flood into the weekend
  • Near Romayor: Cresting near the fifth highest crest on record, highest since May 1990
  • At Liberty: Already topped previous record from Oct. 12, 1994; several subdivisions above Liberty flood, as well as extensive flooding of much of Liberty County
  • Near Moss BluffAlready topped previous record from June 3, 2016
The nearby Menard Creek near Rye also topped a previous record crest from October 1994.
Elsewhere near the immediate Houston metro:
Brays Bayou on the city's southwest side crested over 3 feet higher than the Tax Day 2016 flood. Greens Bayou on the city's east side and near the Eastex Freeway crested initially well below Allison's 2001 levels.
(MORE: Three Reasons Slow-Moving Tropical Storms and Hurricanes Are the Worst)

Brazos River

The Brazos River is expected to crest nearly 2 feet above the previous record set just last June at Richmond, Texas. Mandatory evacuations have been ordered in Fort Bend County.
  • At Richmond: Forecast record crest by late Thursday or Friday topping June 2, 2016, crest; may stay above flood stage well into the following week
  • Near Rosharon: Cresting similar to June 4, 2016, crest; third highest on record; little fall in levels through the Labor Day weekend
  • Near West Columbia: Breach in levee near Columbia Lakes Tuesday makes forecast uncertain; not expected to crest until this weekend
Just to the west, record flooding has also occurred on the San Bernard River near Boling, shattering a previous record from June 1960, and downstream near Sweeny, crushing the previous October 1998 record crest.
(MORE: Your Vehicle Can Be the Biggest Danger in a Flood)

Above: Interactive map showing mandatory (red) and voluntary evacuation zones in Ft. Bend County, Texas (Credit: Ft. Bend County Office of Emergency Management)

Colorado River

  • Near Smithville: Crested at highest level since Oct. 18, 1998; has fallen quickly below flood
  • Above La Grange: Crested at third-highest level, and highest since Dec. 5, 1913; falling quickly
  • At Columbus: Crested at fourth-highest level, highest since July 26, 1938; will fall quickly the rest of this week
  • At Wharton: Cresting at second-highest level, highest since Dec. 13, 1913; drops below flood stage over the Labor Day weekend
  • Near Bay City: Crest Thursday or Friday at eighth-highest level, highest since June 1960; falling quickly into the Labor Day weekend
Much of the west and southwest sides of Wharton, Texas, are expected to be under water from the Colorado River. The river may overtop levees by several feet in Bay City.

Guadalupe River

The Guadalupe River is flooding parts of the city of Victoria. Upstream, the west side of the town of Cuero may experience disastrous flooding, potentially forcing all roads to be shut down into town except Highway 87. Near Thomaston, hundreds of homes may be flooded to over 10 feet, according to National Weather Service accounts of previous floods.
  • Near Cuero: Crested Tuesday among the top three crests on record, highest since Oct. 20, 1998; capable of disastrous flooding in the area
  • At Victoria: Forecast crest near second-highest level early Thursday, but about 2.6 feet lower than October 1998 crest, with only a slow fall into the Labor Day weekend
  • Near Bloomington: Forecast crest late this week topped only by Oct. 21, 1998, crest, with only a slow fall into next week
(MORE: Water, Not Wind, the Deadliest Factor in U.S. Tropical Storms, Hurricanes)

East Texas/Western Louisiana

It will be an arduously slow process to first get coastal water levels down, then drain the massive volume of floodwater upstream. This process will likely continue past Labor Day in some areas.
Check back with for updates on Harvey.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

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