Hurricane Bonnie Landfalling Observed From ER-2 doppler radar on 26 August 1998 During CAMEX-3

Hurricane Bonnie was over flown on 26 August 1998 by the NASA ER-2 aircraft instrumented with an X-Band radar (EDOP) and several radiometers. EDOP is a fixed dual-beam radar which allows for the computation of both vertical and horizontal winds along the aircraft track. Unlike other measurements, ER-2 tracks across a hurricane and intersecting the eye can in principle provide the radial wind component. Flight lines were designed such that 6 lines crossed the eye and outer rain bands of Bonnie at several orientations in a coordinated fashion with the NASA DC-8 and the NOAA P3’s. The ER-2 and DC-8 were stacked closely on top of each other, and the DC-8 and P3 flight tracks were optimized to allow for deployment of dropsondes from these aircraft. Bonnie was near landfall at the time of the overflights, and the inner eyewall underwent a transition just subsequent to the ER-2 departure. The focus of this paper is a preliminary comparison of EDOP-derived vertical and horizontal winds with the DC-8 in situ and dropsonde-derived winds. The passes over Bonnie by the NASA aircraft will be synthesized into a coherent picture of the air flow and precipitation on 26 August, with emphasis on the interesting inflow/outflow regions observed by EDOP.