This story was updated at 2:45 p.m. May 9 with information on Red Cross shelters.

The National Weather Service announced a flash flood watch for all of southeast Texas that will go into effect at 1 p.m. Thursday, May 9, and will remain in effect through 7 p.m. Saturday, May 11.

Rainfall totals are expected to reach 5-8 inches across widespread parts of southeast Texas—including Harris, Montgomery and Fort Bend counties—with totals reaching 9-12 inches in certain isolated areas.

The first round of storms is expected to run from late afternoon on Thursday through Friday morning. A second round of storms could occur late Friday and run through Saturday evening, according to the NWS.

"Soils remain saturated from previous rainfall over the past few days," NWS officials said in a May 9 release. "Any additional rainfall should run off quickly and cause flooding."

Moderate river flooding is ongoing along parts of the San Jacinto, Brazos, San Bernard and Trinity rivers. Officials with New Caney ISD and Fort Bend ISD have also canceled classes for Thursday and Friday.

A flash flood watch is issued by the NWS when conditions are favorable for flash flooding in flood-prone areas. Flash flood watches are different from flash flood warnings, which are issued when a flash flood is imminent.

In urban areas like Houston, the NWS also issues "stay put" alerts when rain falls at a rate of 2-4 inches per hour or 4-8 inches per three hours. During a "stay put" alert, residents are advised not to attempt traveling and to expect flooding at underpasses and low-water crossings.

The Red Cross announced shelter availability at three emergency shelters that have been set up in Harris, Montgomery and Fort Bend counties. Individuals affected by the flood and access the shelters for meals, a dry place to sleep and emotional support.

Shelters have been set up at the following locations:

Harris County
Kingwood First Baptist Church
3500 Woodland Hills Drive, Kingwood

Montgomery County
Bull Sallas Park Friendship Center
21675 McCleskey Road, New Caney

Fort Bend County
Creekside Christian Fellowship
16628 Hwy. 36, Needville

Stay tuned to Community Impact Newspaper for updates on weather, road closures and bayou levels in flood-prone areas throughout the weekend.