This invention concerns an improved forecasting and routing system for scheduling propane and other consumable deliveries as well as service deliveries to end consumers by one or more trucks in a multi-stop environment. The invention utilizes information regarding weather history and the consumption history of individual consumers to calculate their future expected demand, and the variability on that demand when sufficient delivery history is available. Customers lacking sufficient delivery history use the consumption of similar customers as a surrogate. This information serves to determine the near optimal set of successive days within which to replenish or service each customer. Knowing this demand the system assembles deliveries into daily truck delivery routes that maximize the consumables delivered per hour. The system is designed for use in cooperation with a computer having memory and incorporates item, customer, weather, and routing information databases.