Abstract Observations of the cold wake of Cyclone Biparjoy in the Arabian Sea reveal an asymmetrical boundary layer structure across a dense water filament (DWF). This asymmetry arises from the interaction between monsoonal winds and uniquely strong frontal buoyancy gradients. Large‐eddy simulations capture the observed contrast between the downfront wind and upfront wind sides of the DWF, which are respectively destabilized and stabilized by the Ekman buoyancy flux BEk $left({B}{Ek}right)$. Distinct patches of enhanced turbulence on both sides of the DWF indicate multiple triggering mechanisms. While the highest dissipation rates (ε) $(varepsilon )$ occur below the surface mixed layer at the downfront edge–with values exceeding BEk ${B}{Ek}$–dissipation on the upfront side is comparably large despite the nominally stabilizing effect of BEk ${B}_{Ek}$. The frontal‐averaged profile of ε $varepsilon $ on the downfront side deviates from established theories of front‐wind interaction. These findings necessitate a re‐evaluation of frontal turbulence dynamics and their representation in numerical parameterizations.

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