Padre Island is the barrier island that protects Corpus Christi harbor. It is a long low island that extends past its shoreline out into the Gulf of Mexico creating a wide shallow shelf.
The day these were taken there was a 40 mph wind blowing a system in from the Gulf. It was overcast and the waves were breaking as they entered the shelf. It was a roiling sandy/silty mess of water almost thick enough to walk on.
Even so, intrepid surfers were braving the water and waves to find a ride.