Flash Flood Watch: Training Bands of Heavy Storms Could Quickly Drop 4-6 Inches Or More

Jeff Lindner, Harris County Meteorologist just issued an alert concerning increasingly heavy rainfall potential for this evening. And the National Weather Service has issued a FLASH FLOOD WATCH for all counties in the Houston region.

Conditions Right for Heavy Rainfall

“Short range model trends are starting to paint a concerning picture for this evening,” said Lindner, “as a slow-moving, low-level boundary moves into the area and helps to focus a west-to-east oriented line of thunderstorms. Recent trends and high-resolution models suggest potential training bands of heavy rainfall this evening into the overnight hours.”

“Given parameters in place including deep tropical moisture, slowing storm motions, and a good feed of low-level flow off the Gulf, excessive rainfall rates of 2-4 inches per hour will be possible and this will lead to rapid street flooding.”

“If storms anchor or slow over an area for a few hours, the rainfall total could quickly reach 4-6 inches with higher isolated amounts,” said Lindner.

All Houston Region Currently in Danger Zone

Lindner feels all areas within the region may feel the effects. “Everywhere should be ready. As of Noon, I suspect the main focus area will be Waller, Austin, NW Harris, SW Montgomery Counties. But we will have to see how things develop this afternoon.”

For the moment the main concern is street flooding.

The front will lift back northward on Thursday and will likely trigger another round of showers and thunderstorms.

NWS Issues Flash Flood Watch

The National Weather Service in League City has issued a * Flash Flood Watch for portions of south central Texas and southeast Texas, including the following areas, in south central Texas, Coastal Jackson and Inland Jackson. In southeast Texas, Austin, Brazos, Burleson, Chambers, Coastal Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston Island and Bolivar Peninsula, Grimes, Houston, Inland Brazoria, Inland Galveston, Inland Harris, Inland Matagorda, Madison, Matagorda Islands, Montgomery, Northern Liberty, Polk, San Jacinto, Southern Liberty, Trinity, Walker, Waller, Washington and Wharton. *

From 7 PM CDT this evening through Wednesday morning

A line of strong thunderstorms will develop over southeast Texas this evening and slowly move eastward through Wednesday morning. A combination between the slow moving nature of the thunderstorms, back building/training of thunderstorms, and recent rainfall over the area has led to an increasing threat of flash flooding.

NWS predicts rainfall rates may reach one to three inches per hour or more at times.

The NWS also feels uncertainty remains in the timing and location of the line of strong thunderstorms.

On average, two to four inches of rain is expected through tomorrow morning with isolated areas of six to eight inches possible.

These storms with heavy rainfall may be capable of flooding roadways. Low water crossings may flood becoming impassable and dangerous. Small creeks and bayous may see minor rises.


A Flash Flood Watch means that conditions may develop that lead to Flash Flooding. Flash Flooding is a very dangerous situation. You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued.

Posted by Bob Rehak on 6/23/2020

1029 Days since Hurricane Harvey and 278 since Imelda