A nondimensional form of the temperature spectrum in a convective near-surface layer was derived empirically as a function of stability parameter ξ = z/L and surface wave parameter γ = u*/(gz)1/2, under the assumption of horizontal isotropy, where z is the depth of the measurement, L is the Monin-Obukhov length scale, u* is the surface friction velocity, and g is the acceleration due to gravity. The wave number-weighted, one-dimensional spectrum had +1 slope at low wave numbers and -2/3 slope at high wave numbers (characteristic of an inertial subrange). Spectral levels in the -2/3 range varied with γ, and the spectrum width was a function of ξ. The wavelength of the spectral peak decreased as -ξ (>0) increased. The variation of spectral level in the inertial subrange suggested that dissipation due to wave breaking was enhanced by a factor of 1.7 at 2-m depth for a wind speed of 10 m s-1. Root-mean-square temperature fluctuations at 2-m depth versus -ξ were in excellent agreement with atmospheric surface layer observations and agreed moderately well (within 30%) with the results of large-eddy simulation experiments. Root-mean-square fluctuations were proportional to (-ξ)-1/3 for -ξ > 0.4, consistent with the predictions of similarity theory. The skewness of temperature fluctuations varied with -ξ, qualitatively similar to variation in the atmospheric surface layer. The skewness of the horizontal gradient of temperature at 2-m depth varied relative to the wind direction and was well described by a cosine function with amplitude 0.6.