NSF Grant AGS-0910737 supported this work. The DOWs are NSF Lower Atmospheric Observing Facilities supported by Grant AGS-0801041. The authors thank Rita crewmembers for the collection of the DOW and tower data, Curtis Alexander for his DREADER analysis package, Rachel Humphrey for her assistance in preparing the manuscript, and the reviewers for their helpful input.
ASCE, 2010: Wind loads. Minimum Design Loads for Buildings and Other Structures, ASCE Standard Series, Vol. 7-10, ASCE, 241–258.
Balderrama, J. A., and Coauthors, 2011: The Florida Coastal Monitoring Program (FCMP): A review. J. Wind Eng. Ind. Aerodyn., 99, 979–995.
Barnes, S. L., 1964: A technique for maximizing details in numerical weather map analysis. J. Appl. Meteor.,3, 396–409.
Beljaars, A. C. M., 1987: The influence of sampling and filtering on measured wind gusts. J. Atmos. Oceanic Technol., 4, 613–626.
Carbone, R. E., , M. J. Carpenter, , and C. D. Burghart, 1985: Doppler radar sampling limitations in convective storms. J. Atmos. Oceanic Technol.,2, 357–361.
ESDU, 1983: Strong winds in the atmospheric boundary layer. Part 2: Discrete gust speeds. Engineering Sciences Data Unit, Item No. 83045, HIS ESDU, London, United Kingdom.
FEMA, 2006: HAZUS MH MR3 hurricane model technical manual. Mitigation Division, Federal Emergency Management Agency, Dept. of Homeland Security. [Available online at www.fema.gov/library/viewRecord.do?id=3034.]
Franklin, J. L., , M. L. Black, , and K. Valde, 2003: GPS dropwindsonde wind profiles in hurricanes and their operational implications. Wea. Forecasting, 18, 32–44.
Giammanco, I. M., , J. L. Schroeder, , and M. D. Powell, 2013: GPS dropwindsonde and WSR-88D observations of tropical cyclone vertical wind profiles and their characteristics. Wea. Forecasting, 28, 77–99.
Greenway, M. E., 1979: An analytical approach to wind velocity gust factors. J. Ind. Aerodyn.,5, 61–91.
Harris, R. I., , and D. M. Deaves, 1981: The structure of strong winds. Proc. Conf. on Wind Engineering in the Eighties, London, United Kingdom, Construction Industry Research and Information Association, Paper 4. [Available from CIRIA, Classic House, 174–180 Old St., London EC1V 9BP, United Kingdom.]
Hirth, B. D., , J. L. Schroeder, , C. C. Weiss, , D. A. Smith, , and M. I. Biggerstaff, 2012: Research radar analyses of the internal boundary layer over Cape Canaveral, Florida, during the landfall of Hurricane Frances (2004). Wea. Forecasting, 27, 1349–1372.
Kepert, J. D., 2006: Observed boundary layer wind structure and balance in the hurricane core. Part I: Hurricane Georges. J. Atmos. Sci., 63, 2169–2193.
Kosiba, K. A., , J. Wurman, , and P. Robinson, 2012: Fine-scale Dual-Doppler analysis of the boundary layer in Hurricane Frances (2004). Proc. 30th Conf. on Hurricanes and Tropical Meteorology, Jacksonville, FL, Amer. Meteor. Soc. [Available online at https://ams.confex.com/ams/30Hurricane/webprogram/Paper205990.html.]
Lorsolo, S., , J. L. Schroeder, , P. Dodge, , and F. Marks, 2008: An observational study of hurricane boundary layer small-scale coherent structures. Mon. Wea. Rev., 136, 2871–2893.
Majcen, M., , P. Markowski, , Y. Richardson, , D. Dowell, , and J. Wurman, 2008: Multipass objective analyses of Doppler radar data. J. Atmos. Oceanic Technol., 25, 1845–1858.
Masters, F. J., , H. W. Tieleman, , and J. A. Balderrama, 2010: Surface wind measurements in three Gulf coast hurricanes of 2005. J. Wind Eng. Ind. Aerodyn., 98, 533–547.
Morrison, I., , S. Businger, , F. Marks, , P. Dodge, , and J. A. Businger, 2005: An observational case for the prevalence of roll vortices in the hurricane boundary layer. J. Atmos. Sci., 62, 2662–2673.
Powell, M. D., , and S. H. Houston, 1996: Hurricane Andrew's landfall in south Florida. Part II: Surface wind fields and potential real-time applications. Wea. Forecasting, 11, 329–349.
Powell, M. D., , S. H. Houston, , and T. A. Reinhold, 1996: Hurricane Andrew's landfall in south Florida. Part I: Standardizing measurements for documentation of surface wind fields. Wea. Forecasting, 11, 304–328.
Powell, M. D., , P. J. Vickery, , and T. A. Reinhold, 2003: Reduced drag coefficient for high wind speeds in tropical cyclones. Nature,422, 279–283.
Rice, S. O., 1954: The mathematical analysis of random noise. Noise and Stochastic Processes, N. Wax, Ed., Dover Publications, 133–294.
Simiu, E., , and R. Scanlan, 1996: Wind Effects on Structures: Fundamentals and Applications to Design. 3rd ed. John Wiley and Sons, 688 pp.
Smith, R. K., , and M. T. Montgomery, 2013: On the existence of the logarithmic surface layer in the inner core of hurricanes. Quart. J. Roy. Meteor. Soc., doi:10.1002/qj.2121, in press.
Vickery, P. J., , D. Wadhera, , M. D. Powell, , and Y. Chen, 2009: A hurricane boundary layer and wind field model for use in engineering applications. J. Appl. Meteor. Climatol., 48, 381–405.
Wurman, J., 2001: The DOW mobile multiple Doppler network. Preprints, 30th Int. Conf. on Radar Meteorology, Munich, Germany, Amer. Meteor. Soc., 95–97.
Wurman, J., , J. M. Straka, , E. N. Rasmussen, , M. Randall, , and A. Zahrai, 1997: Design and deployment of a portable, pencil-beam, pulsed, 3-cm Doppler radar. J. Atmos. Oceanic Technol., 14, 1502–1512.
The measurement was taken at approximately 9.8 m MSL over marshland.
Refineries north of the DOW deployment site contained structures that blocked the radar beams below 0.5°–1.0° in a majority of the sectors. A few small sectors were obstructed even at 1.2° elevation and data from these sectors were removed from the analysis.
Data were not taken at multiple elevations, so the height dependency of the characteristic size cannot be assessed. Although an increase in characteristic size with height cannot be ruled out, the change in radar beam height from 2- to 5-km range was only 60 m, implying that the observed increase in scale was not due to beam height variation.
A 50-m patch represents an average of the radar data within a 50-m radius of a given location.
The 0800 to 0900 UTC interval was excluded because the wind direction varied appreciably during this period.
The assumption of a neutrally stable boundary layer is based on the nocturnal hurricane environment; specifically, the boundary layer should be well mixed due to the overturning associated with the rolls/streaks and there should be little net surface heating–cooling due to cloud cover.
As discussed earlier, while the upstream fetch does influence the wind speed at a particular location, due to the complex terrain and the likely development of multiple internal boundary layers, the distance of the upstream influence is unknown so the local surface roughness values were used to construct these maps.