Normalized difference vegetation indices (NDVI), calculated from Landsat‐MSS images, were correlated with monthly total precipitation and estimates of monthly evaporation in a prairie environment. The highest value of the correlation coefficient (r=.80) was obtained between the monthly mean NDVI and estimated evaporation of the preceding month. The de‐seasoned NDVI and evaporation values retained a correlation coefficient of .53 corresponding to half of the originally explained variance (r²=.64) between NDVI and evaporation suggesting that NDVI indices may be useful for estimating regional‐scale evaporation in a water‐limited environment.