Flash Flood in Jim Wells County, Texas

Water over road at CR 211 east of Hwy 281.

A significant flash flooding event began across South Texas on June 15, 2026 as an exceptionally moist tropical air mass overspread the region ahead of a slow-moving frontal boundary and an upper-level disturbance lifting out of northern Mexico. Deep tropical moisture associated with the remnants of former Tropical Storm Cristina and a developing low-pressure area near the Texas coast pushed precipitable water values into the 2.3-2.7 inch range, near or above daily record levels and roughly three standard deviations above normal for mid-June. At the same time, abundant instability, saturated atmospheric profiles, and deep warm cloud layers supported highly efficient rainfall production, with rainfall rates frequently reaching 2-4 inches per hour and locally approaching 5 inches per hour. A slow-moving mesoscale convective system that had developed farther north sagged southward into South Texas while repeated bands of thunderstorms trained over the same locations along the frontal boundary and zones of strong low-level moisture convergence. Weak steering currents and persistent inflow from the Gulf allowed storms to repeatedly redevelop over affected areas, producing localized rainfall totals of 3-5 inches in only a few hours and ultimately widespread totals of 4-8 inches. The combination of extreme rainfall rates, repeated training convection, and prolonged moisture transport resulted in dangerous flash flooding across portions of the Coastal Plains, Coastal Bend, Rio Grande Valley, and surrounding areas.