The variability of the circulation over the inner-shelf off the South Padre Island is investigated with a combination of Eulerian (CTD casts) and Lagrangian (drifters) observations obtained during November 2016 and 2017 within 12km from the coast. In absence of atmospheric or larger scale forcing, typical stratification in the inner-shelf is cold and fresh upper layer due to inflow from Laguna Madre and warm and salty bottom layer (far field oceanic water). On November 8 2016 the passage of a cold front or Norte cooled down the atmospheric temperature by ~5ºC resulting in ebb tide outflow through the Port Isabel inlet of fresh but very cold water into the inner shelf. The fresh plume was ~2ºC cooler than the well-mixed nearshore waters found the day before. As a result, a retrograde front with isopycnals sloping downward towards the coast developed with a jet centered at roughly 8 km offshore on November 12. Light (dense) waters were found nearshore (offshore) driving a geostrophic southward flow in balance with the bottom intensified cross-shelf density gradients. Westward Ekman transport during downwelling regime drove onshore displacement of the outcropping retrograde front. During autumn-2017 experiment the opposite scenario occurred. The prevailing winds were northward (Suradas) favoring upwelling with offshore displacement of the frontal interface. Upwelled water was warm but saltier than that offshore leading to heavy (light) water nearshore (offshore) which triggers a surface intensified geostrophic current northward. The current jet was again centered at 8 km from the shore. We conclude that the inner-shelf off the South Padre Island is controlled by two main modes of along-shelf circulation driven by cross-shelf density gradients in qualitative agreement with the modeled inner-shelf circulation discussed in Austin and Lentz (2002; J. Phys. Oceanogr., 32). Two exceptions to these modes associated with plume-induced submesoscale instabilities are also shown.