IBHS News Releases

Wind Speed Data Shows Category 1 in Pensacola, Category 2 Near Perdido

Tampa - For the first time ever, homes instrumented as part of the Florida Coastal Monitoring Project (FCMP) have captured wind pressure data on buildings subjected to the direct impact of hurricane force winds.

The Florida Department of Community Affairs (DCA) initiated the FCMP six years ago in an effort to determine the true level of hurricane events in residential areas, and to assess the performance of various protection measures in reducing damage.  Partners in the project include engineers and specialists from the University of Florida, Florida Institute of Technology, Clemson University and Florida International University.

House monitoring systems were deployed on six homes in Hurricanes Frances and Ivan to understand wind speeds and wind effects of the storms.  Additionally, four mobile meteorological towers were deployed with funding assistance from NOAA’s Florida Hurricane Alliance and Florida Sea Grant.

The instrumentation systems and mobile towers were developed with South Carolina Sea Grant Consortium funding, under the direction of Dr. Timothy Reinhold, vice president of engineering at the Institute for Business & Home Safety (IBHS), who was then a professor of Civil Engineering at Clemson.  Team members have added numerous enhancements to the working system.  Deployments are handled as a team effort by faculty and students from the various institutions with assistance from IBHS.*

The FCMP represented the first opportunity to implement these systems in the field, and Clemson and UF have worked as a team in developing the FCMP since its beginning.  Deployments are handled as a team effort from the various institutions with assistance from IBHS.  Until now, winds at the houses only approached tropical storm levels. 

Preliminary data during Frances includes:

• The highest 3-second gust winds measured in Hurricane Frances were 106 mph at an open exposure site south of Fort Pierce. 

From Hurricane Ivan:

• A house 3 miles east of Big Lagoon State Park in the Florida Panhandle was subjected to 91 mph gust winds in the eastern eyewall of Hurricane Ivan.  These 3-second gusts were measured in a suburban area at a height of 21 feet.  (The equivalent 33 feet 3-second gust speeds for a corresponding open exposure location, typical meteorological reference conditions, correspond to 117 mph.  This equivalent 117 mph gust speed represents the highest wind speeds reported to date from any of the various meteorological stations deployed in the region.) 
• A sonic anemometer operated by the University of Oklahoma reported a 109 mph gust at Gulf Shores Airport.
• An FCMP tower near Fairhope, AL reported a gust speed of 90 mph and clearly experienced the passage of the eye.  
• An FCMP tower at the Pensacola Airport reported a peak gust of 106 mph in open terrain.  
• A house toward the Eastern end of Gulf Breeze was subjected to 82 mph gust winds.  These 3-second gusts were measured in a suburban area at a height of 19 feet.  (The equivalent 33 feet 3-second gust speeds for a corresponding open exposure location would be 109 mph.)
• Houses in Navarre and Destin were subjected to winds that correspond to about 75 mph 3-second gusts at 33 feet elevations in open exposure locations.

The various ground-based measurements are providing a detailed and consistent view of the wind field in the area.  Since hurricane categories are based on sustained one-minute winds, which are about 20-30% lower than the gust values, the results clearly indicate that most of the Pensacola mainland saw winds that correspond to a category 1 storm, not the category 3 or higher intensity winds being widely reported. 

Also in the Panhandle, a small area near Perdido and a larger stretch of the barrier islands probably saw winds corresponding to a weak category 2 storm.  Much like Hurricane Opal in 1995, Ivan seems to have lost much of its wind punch as it approached shore while the surge remained at category 3 levels or higher. 

As widespread as the destruction was in the Pensacola area and as devastating as it is to homeowners, in most cases, if a tree did not fall on the house, water enter through loss of roof covering or a puncture in the building envelope, the direct wind-related damage was relatively light during Ivan. 

There were spectacular failures of poorly connected, poorly maintained or poorly built buildings.  Along the coastlines, there was significant surge damage, the major impact of Ivan.  However, if the storm had come in as a category 3 or stronger, wind damages would have been much worse.

Ultimately, research partners will study the house data in an effort to further validate wind tunnel modeling techniques and assess the accuracy of building code provisions for defining wind loads in hurricane prone regions.  These unique data sets will also be made available to researchers around the world.

The tower wind speed data is posted to a public web site in real-time when conditions allow transmission.  Visit the FCMP web site to learn more: www.ce.ufl.edu/~fcmp

*For a list of contacts at each participating institution, please contact Wendy Fontaine at (813) 675-1045.