Houston could experience flash flooding through Memorial Day, forecasters say. Why it matters: Your long weekend plans might be a wash. Threat level: The latest National Weather Service forecast indicates the flood risk is highest on Saturday for Houston and much of Southeast Texas but lasts through at least Monday.

After isolated rain chances on Thursday, more widespread rain and potential flooding will enter South Texas' forecast on Friday.

"Cities don't just change the landscape, they change the weather."

Some of the holiday weekend storms will be strong but not severe, so the weather threat will be limited to mostly heavy rainfall and flash flooding.

Meteorologists are warning of the potential for severe weather across the state.

More than 33 million Americans are in the bull's eye of a mounting flash flood threat across parts of Texas and the South that is expected to increase through Memorial Day weekend.

Severe storms have thousands of CenterPoint Energy customers without power across the Houston area, with the most significant impact in southwest Houston as of 2 p.m. Saturday.