Figure 6. GOES-12 visible image of Hurricane Katrina over the central Gulf of Mexico at 1745 UTC 28 August 2005, near the time of its peak intensity of 150 kt.
A) 2000 UTC 28 August B) 1000 UTC 29 August Figure 7. Airborne Doppler radar-derived wind speed cross sections obtained from a NOAA WP-3D Hurricane Hunter aircraft at approximately (a) 2000 UTC 28 August 2005 and (b) 1000 UTC 29 August 2005. Radial distance from the center of the hurricane increases to the right, and both cross sections extend toward the east from the center of the hurricane. Wind speeds are in meters per second (m/s) as indicated by color shades with legend beneath the diagrams. Wind speeds derived from the radar extend down to about the 300 m level. Note the broad and elevated wind maximum in the 2-4 km layer on 29 August (centered near the 700 mb flight level), which was not present on 28 August when the maximum winds were concentrated at the more typical location near the top of the boundary layer (~500 m). The 65-69 m/s winds in the 300-500 m layer in panel (b), in the isolated area at a radius of 50-55 km from the center, correspond to no more than about 105 kt winds at the surface, using an average adjustment of the mean boundary layer winds to the surface. Graphics courtesy of the NOAA Hurricane Research Division (HRD).
1 The county NFIP losses are multiplied by the estimated county penetration rates for the highest flood risk area using the Federal Emergency Management Agency (FEMA) special flood hazard area (SFHA, e.g. the 100-year base flood plain) for a more accurate estimate. This estimate should still be conservative for total flood damages because most homeowner’s policies are capped at $250,000 and areas outside of the SFHA can also experience significant flooding.
2 NOAA Technical Memorandum NWS NHC-6, “The Deadliest, Costliest, and Most Intense United States Tropical Cyclones from 1851 to 2010”. Revised August 2011.
