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Sensible heat flux (H) is a critical and crucial energy partitioning component. Its estimation at local and regional scale generally uses surface radiometric temperature from observations in thermal infrared bands as well as aerodynamic resistance determined from ground-based measurements. A study was carried out to compute daily instantaneous sensible heat fluxes from MODerate resolution Imaging Spectroradiometer (MODIS) TERRA and AQUA optical and thermal data at morning (11:00-11:30hrs) and noon (13:00-13:30hrs) hours, respectively. MODIS data were acquired over semi-arid wheat-fallow system at Nawagam, Kheda district of Gujarat during 1 November 2006 to 31 May 2007: A numerical iterative procedure built-in METRIC (Mapping Evapotranspiration at high. Resolution and with Internalized Calibration) model that takes inputs from 'dry' and 'cold' pixels, was' used to solve stability-instability parameters and aerodynamic resistance in a single source energy balance framework. In addition, Richardson number based bulk approach was also used to derive such parameters. MODIS based estimates from both the approaches were compared with area-integrated half-hourly measured fluxes from Large Aperture Scintillometer (LAS) installed at 10m height with a path length of 1.5km between its transmitter and receiver. Initial analysis showed low root mean square error (RMSE) of METRIC estimates as compared to bulk approach. The RMSE of TERRA and AQUA based H estimates from METRIC were 21Wm-2 (19%) with R2 = 0.85 (n = 157) and 22Wm-2 (14%) with R2 = 0.9 (n = 133) when compared to coincident area integrated H measurements from LAS, respectively. The RMSE of TERRA-AQUA pooled H estimates was found to be 21.5Wm-2 (17%) with R2 = 0.88 (n =278). The Simulated half-hourly heat fluxes from a two-source Atmosphere Land Exchange (ALEX) model were also compared with satellite based estimates and LAS measurements after sensitivity analysis. Comparison among model simulation, METRIC estimates and LAS measurements showed that METRIC (satellite based) estimated was better than simulated sensible heat flux.