Information from Dr. Masters regards to Hurricane Ike

Source

Track forecast for Ike
A trough of low pressure is currently passing to the north of Ike, and this trough has been able to turn Ike north of due west. Ike is now moving west-northwest, and this motion is expected to continue today. By Wednesday, Ike is expected to take a more westerly motion again, as high pressure to the north builds in. As Ike approaches Texas on Friday, a new trough of low pressure is expected to pass to the north, potentially turning Ike to the northwest.

The latest 12Z (8am EDT) computer models have come into much better agreement. With the exception of the NOGAPS model, which targets Brownsville, all of the major models foresee a landfall between Corpus Christi and Galveston. Landfall would occur Friday night or Saturday morning, and tropical storm force winds would arrive at the coast on Friday morning. Given the inability of the models to agree until now, this landfall is certainly not a "sure thing", and the cone of uncertainty covers the entire coast of Texas. Data from the NOAA jet will go into tonight's 00Z (8 pm EDT) model runs, which will be available first thing Wednesday morning. That set of model runs should give us a pretty good idea of where Ike will go. I'm sure emergency managers are not eager to call for an evacuation of Houston, after the debacle of the evacuation for Hurricane Rita in 2005. Over 110 people died in the evacuation--far more than died in the storm. Still, there is a significant chance that an evacuation of large stretches of the Texas coast--including portions of Houston--will have to be ordered on Wednesday or Thursday.

A realistic worse-case scenario for Texas
There is a significant chance that Ike will be the worst hurricane to hit Texas in over 40 years. The latest run of the HWRF and GFDL models paint a realistic worst-case scenario for Texas. These models bring Ike to the coast as a Category 4 hurricane (which I give a 20% probability of happening). The HWRF predicts a 170-mile stretch of coast will receive hurricane force winds of 74 mph or greater. A 100-mile stretch of coast will receive winds of Category 3 strength and higher, 115 mph. Hurricane force winds will push inland up to 50 miles, along a 50-mile wide region where the eyewall makes landfall. A 100-mile stretch of Texas coast will receive a storm surge of 10-15 feet, with bays just to the right of where the eye makes landfall receiving a 20-25 foot storm surge. This is what Hurricane Carla of 1961 did to Texas. Carla was a Category 4 hurricane with 145 mph winds at landfall, and drove a 10 foot or higher storm surge to a 180-mile stretch of Texas coast. A maximum storm surge of 22 feet was recorded at Port Lavaca, Texas. Despite the fact that the center of Carla hit over 120 miles southwest of Houston, the hurricane drove a 15-foot storm surge into the bays along the south side of the city.

Texas is highly vulnerable to storm surge
The Texas coast is highly vulnerable to large storm surges, due to the long expanse of shallow Continental Shelf waters offshore. The shallow depths allow large the swirling winds of the hurricane to pile up huge mounds of water, which then sweep inland when the hurricane makes landfall. Even Category 1 hurricanes are capable of generating 15 foot storm surges along some sections of the Texas coast. For example, the August 29, 1942 hurricane hit near Port O'Conner, Texas as a Category 1 storm with 80 mph winds. However, this hurricane had been a Category 3 storm with 115 mph winds the day before landfall, allowing it to pile up a large storm surge over the Continental Shelf just offshore the central Texas coast. The storm weakened suddenly in the 12 hours before landfall, but brought a storm surge characteristic of a Category 2 or 3 hurricane to shore. A 10-15 foot storm surge came ashore over a 100-mile stretch of coast between Port O'Conner and Freeport (Figure 4). Typical maximum storm surge values from a Category 4 hurricane hitting the central Texas coast at high tide are much higher, about 20-25 feet.