Recording current meter data from a 43-day period in the summer of 1977 are used to investigate long-shore coherence at three study sites along the central and lower Texas coast in the northwestern Gulf of Mexico. Mid-depth current data from inner shelf waters reveal an alternating longshore motion that is coherent with the longshore component of the wind stress. Current reversals occur over time scales of the order of 1--2 weeks, but there is a net displacement into the north-northeasterly quadrant at all three locations. Transient periods of convergence and divergence are suggeted between adjacent study sites as a result of not quite simultaneous reversals in longshore motion, o gradients in longshore motion in the same sense. Spectral analysis of the longshore current components indicates that motion is very nearly in phase along this part of the coast and that the flow is highly coherent over time scales in excess of about 3 days. |