The green line on this graph indicates that the water level at S Padre Island Coast Guard Station is between 2 and 3 feet above normal. This line measures the difference between predicted water levels (blue) and actual water levels (red), which essentially defines the storm surge.
Alex's eye is now visible on Brownsville's radar. Also, the wind at South Padre Island, TX at 1300 CDT shifted from the ENE at 35 MPH, an indication that Alex is approaching the coast. Surge levels should continue rising this afternoon.