The association between ∼10-km scale horizontal variation of radiometric surface temperature (T_s) and aircraft-derived fluxes of sensible heat (H) and moisture (LE) is the focus of this work. We use aircraft, surface, and satellite data from a Cooperative Atmospheric-Surface Exchange Studies (CASES) field program, which took place in the southern part of the 60 × 100 km Walnut River (Kansas) watershed from 22 April to 22 May 1997, when winter wheat matured and prairie grass greened up. Aircraft T_s observed along repeated flight tracks above the surface layer showed a persistent pattern: maxima over ridges characterized by shallow soil and rocky outcroppings and minima over riparian zones. H and T_s reached maxima in the same longitude zone on two flight tracks 40 km apart. Satellite T_s data from March to June reveal similar persistent patterns with minima more persistent than maxima. Two mechanisms are suggested to explain the association of H and T_s maxima: (1) for winds between 6 and 8 ms⁻¹, modulation of the surface energy budget by vegetation effects; or (2) for winds equal to or below 4 ms⁻¹, a thermally driven circulation centered on T_s maxima. Both mechanisms were possibly enhanced by increased static instability over the T_s maxima. Owing to the small sample available, these results are suggestive rather than conclusive. Effects of rainfall and vegetation on watershed-scale T_s gradients are also explored.