Widespread 1 to 3 inches of rainfall has already fallen in the last 12 hours. A swath of 3 to 5 inches has been observed from Colorado County to NW Harris County. Waves of showers and storms will continue to produce rain rates of 1 to 2+ inches per hour through the evening hours. Training of cells and short duration intense rainfall may cause localized flooding. The Flood Watch is in effect until 3AM Saturday morning. * WHAT...Flooding caused by excessive rainfall continues to be possible. * WHERE...A portion of southeast Texas, including the following areas, Austin, Brazos, Burleson, Coastal Harris, Colorado, Fort Bend, Grimes, Inland Harris, Madison, Montgomery, Northern Liberty, Polk, San Jacinto, Southern Liberty, Trinity, Walker, Waller, Washington and Wharton. * WHEN...Through late tonight. * IMPACTS...Excessive runoff may result in flooding of rivers, creeks, streams, and other low-lying and flood-prone locations. * ADDITIONAL DETAILS... - Waves of showers and storms continue to produce localized high rain rates and the potential for several inches of rain in a short time. - http://www.weather.gov/safety/flood