Proactive event processing constitutes the next phase in the evolution of complex event processing. Proactive event processing makes it possible to anticipate potential issues during process execution and thereby enables proactive process management. One industry domain that can expect relevant benefits from applying proactive event processing is transportation. Transportation companies face numerous stochastic issues when managing the shipment of goods. One such issue faced in airfreight is the exact volume, weight, and number of pieces that a shipper wants to have shipped. Because of the high cost of air shipments, discrepancies between what has been booked by a shipper and the actual volume that is delivered impose costs that create problems for all participants in a shipment. One potential approach to addressing this problem is to use real-time monitoring and proactive alerting to assist air freight companies in anticipating actual delivered weights, volumes, and piece counts. In this paper we address the issue of cargo shipments by leveraging real-time monitoring data collected from an industry-standard monitoring system of a large freight forwarding company. Our evidence indicates that by using a novel proactive event-driven software engine, prediction about the weight of shipments can be developed and used in a proactive manner to assist air freight planners in making better estimates and plans for the shipment of goods. We demonstrate that through the use of this proactive approach, predictions concerning over- and under-weight loads can be made days in advance of a shipment, thus enabling the air freight planner to optimize their load plans and thus maximize the revenue that they generate from shipments. Copyright © 2013 ACM.