Update, 6 PM, August 27^th
Scattered to locally numerous thunderstorms developed across the Lower Rio Grande Valley by late morning, and covered a good deal of the region by mid to late afternoon, dropping a radar estimated 3 inches or more (right) in flood prone areas along the Cameron/Hidalgo County line, which cause street flooding in La Feria. Other heavy rains soaked southwest Kenedy County. At 6 PM, most of the storms closer to the coast had faded to light rain or cloud cover; however, stronger cells were just west and southwest of Zapata and Starr County.

Weekly Forecast and Reasoning
There will be no rest for the weary through Friday, and perhaps into Saturday, August 30^th, as deep tropical moisture lurks over or near the entire Lower RGV. Weak upper level disturbances sliding into northeast Mexico and the Rio Grande Valley and Rio Grande Plains near the Texas and Mexico border will enhance the potential for heavy rainfall, particularly along and near the Rio Grande itself. Elsewhere, the continuation of deep moisture along with daytime heating and old thunderstorm boundaries acting as foci, will allow more banded showers and storms from late morning into the afternoon. Should these storms track across areas such as extreme eastern Hidalgo, western Cameron, and southwestern Willacy County, local flash flooding could redevelop.

Across the western Lower Rio Grande Valley, numerous mainly afternoon into nighttime showers and thunderstorms are expected, as boundaries from activity farther east combined with air mass differences get things going. Nighttime activity will be highly dependent on the location, intensity, and movement of storms that develop along and near the Sierra Madre Oriental in northern Mexico. Boundaries from such storms, combining with activity that moves northwest from Hidalgo, Cameron, and Tamaulipas, Mexico, would produce small but potent complexes, which, if occurring over previously flooded areas, could bring a return of flash flooding in a hurry. Just a couple of inches of rain in an hour will aggravate the situation. Current data suggest another 2 to 4 inches, with locally 6 inches or more in heavier bands, across these areas through August 30^th. Stay tuned for additional updates as this next round of inclement weather unfolds.

Continue to monitor this website for updates to the overall forecast, including additional flood watches, warnings, and advisories. And remember, never cross flooded roadways of unknown depths. The life you save may be your own. Turn around, Don't Drown^TM! For complete information on flood safety, click here.