In order to place the observations in a storm-relative framework, the start of the warm sector, the surface cold-frontal passage, and the end of the post-frontal sector were defined from basic meteorological parameters. The storms' movements produce a northeast-to-southwest section through each storm. With these definitions, statistical composites of storm-relative atmospheric parameters, surface fluxes, and wave characteristics were computed for each ship. The results include: a) the momentum flux maximizes just before the frontal passage during the peak in wind speed associated with the warm-sector low-level jet. A second stress maximum of comparable magnitude occurs in the middle of the post-frontal regime for the data from the R/V Knorr but not from the Suroit. b) The latent and sensible heat fluxes are a minimum just before the frontal passage. Despite the strong surface winds at this time, the moistening and warming associated with synoptic-scale advective patterns and surface fluxes minimize the vertical gradients in specific humidity and temperature. This pattern should affect the surface potential vorticity generation, which has dynamical implications for frontal stability. c) Wave heights increase steadily from near the eastern edge of the warm sector to just before frontal passage, remaining high through most of the post-frontal regime before decreasing. d) Differences between covariance and inertial dissipation fluxes are largest during the times bracketing the cold front when the wave heights are large (the covariance fluxes are larger), and e) the stress direction is consistently 5-10° to the right of the wind direction in the warm sector and 2-15° degrees to the left of the wind direction in the post-frontal regime. This last result implies that satellite-based scatterometer wind directions, which rely on the surface stress field, will underestimate the surface directional wind shift across the front. One case study with simultaneous observations from NOAA P-3 aircraft and a QuikScat satellite overpass during the PACJET 2001 field experiment illustrates this bias in the satellite-determined wind directions.
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