Hurricane Katrina on 25 August 2005 : airborne radar observations and numerical modeling

Landfall of Katrina as a category-1 hurricane over Miami (Florida) on Aug. 25th, 2005 was not as severe as it was over New-Orleans (Louisiana) on the 29th, but it caused a significant amount of damages in this area. The characteristics of this event were (i) a rapid intensification in the hours prior to landfall, (ii) a change in storm motion once it arrived over South Florida, (iii) the large cumulated rainfall associated with the eyewall.

I will present results from the analysis of airborne radar data collected during a mission flown by the NOAA N43RF P3 aircraft during the afternoon of Aug. 25th. The evolution of the reflectivity and Doppler-derived tangential, radial and vertical velocity fields will be discussed. In parallel, the non-hydrostatic multi-nested MesoNH model, initialized with a Doppler-derived bogus vortex, is used to simulate hurricane Katrina. If available, comparisons between modeled and observed characteristics will be discussed.