We present a model intended to predict mainly the residential and commercial natural gas consumption in urban areas, for the short and intermediate ranges of time. In the short range, the model has been successfully used to forecast the daily gas consumption of major cities of Argentina. It is able to predict the consumption 1 to 5 days in advance with 10% of uncertainty. In the intermediate range (1 to 5 years), the model allows us to estimate the annual peak consumption, load factors and the optimal transportation capacity for a given region of interest. We also present a novel procedure to obtain the distribution of daily consumption from the monthly consumption obtained from the monthly billing.