Evacuations based on storm surge not wind
New hurricane maps shrink evacuation zones, but not the risk for those outside the zones (Corpus Christi Caller-Times)
New maps adopted by the state before last year’s hurricane season take wind out of the equation, relying only on models of storm surge, the deadliest of a hurricane’s destructive forces. Now the city’s zones extend only to Weber and Chapman Ranch roads for the strongest storms. Also, now the state maps refer to the zones as evacuation zones rather than risk zones.
The shift marks a change in thinking toward a “run from the water, hide from the wind” philosophy to which the National Hurricane Center and officials along much of the country’s coastline subscribe.
“You want to evacuate as few people as possible,” National Weather Service meteorologist John Metz said. “It’s disruptive to society, and it’s expensive. You want to minimize that as much as possible, but at the same time you don’t want to risk lives.”
Evacuating more people than necessary can create a mess of problems as we saw with the evacuation during the approach of Hurricane Rita in 2005. While the overall evacuation was successful in emptying Galveston County, the roads were clogged with people who lived on the north and west sides of Houston and were on higher ground that did not need to be evacuated. When officials saw the destruction caused by Katrina, there was a level of panic and everyone was told to leave. 3 million people evacuated when only 1.5 million lived in the effected areas. I remember taking 16 hours to make a normally 4 hour drive from Galveston Bay area to the Hill Country.
Based on the lessons learned from Rita, the National Hurricane Center adopted the "Run from the water, hide from the wind" philosophy.
This does not mean that people who are not told to evacuate are out of danger. On the contrary, wind damage can be quite severe during even a low level hurricane or tropical storm. It is crucial to bring in all loose objects and tie down anything that isn't already anchored to the ground.
Finally, when the storm hits, hunker down in a windowless room in the center of the house. Preferably a small closet or bathroom or under the stairs. The potential for tornadoes or intense straight-line winds causing damage can be high. It's not necessary to leave the area but you must take measures to protect yourself.
Finally, remember that the officials cannot force you to stay in your house. If you do not feel safe or if you live in a mobile home, or if your neighborhood typically floods during a spring shower then by all means LEAVE.
The intent is to prevent the roads from clogging and to prevent a panic. A few extra people on the road is a lot different than a few million.