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Emily makes landfall

By: Dr. Jeff Masters, 1:15 PM GMT on July 20, 2005

The eye of Hurricane Emily made landfall at 635 am CDT this morning along the northeastern coast of Mexico about 3 miles south of Boca Madre, which is 75 miles south of Brownsville, Texas. Emily had 125 mph winds and a central pressure of 944 mb at landfall, making it a Category 3 hurricane.

Emily managed to hold together and not weaken after yesterday's rapid intensification cycle. I had speculated that the slow movement of the hurricane would stir up cooler waters and cause weakening, and that the cooler waters next to the coast might also weaken the storm. That did not happen, apparently since the other environmental factors (weak wind shear, good upper level outflow) were strong enough to overcome the cooler waters. Mexico was unfortunate to have the storm slow down and make landfall at peak intensity. The slow motion of the storm means that the coast will be exposed to a long period of high water and battering waves. However, this portion of the coast is sparsely populated. Browsville is just north of the area of hurricane force winds, but the coastal areas will take a severe pounding from Emily's storm surge. The rains of Emily, expected to bring 2 - 4 inches to South Texas, will be most welcome, as this part of Texas is under extreme drought.

Emily was undergoing a eyewall replacement cycle at landfall. If one looks at the last VORTEX report from the Hurricane Hunters, one sees the item: "M. CO15-50". This means concentric eyewalls, with the inner eyewall 15 nautical miles in diameter and the outer eyewall 50 nautical miles in diameter. This is the situation that happened several times during the course of both Emily's and Dennis' lives. As a hurricane intensifies and spins tighter and tighter, the eyewall contracts until it is no longer stable and collapses, and a new outer eyewall takes over. I've annotated a radar image below to show the concentric eyewalls of Emily at landfall.



The Brownsville 248 nm mile range radar will be interesting to watch today as Emily moves inland and the eyewalls collapse.

Dr. Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.