An arrangement for monitoring an aseptic manufacturing process includes product condition sensors capable of making closely spaced measurements of a product condition such as temperature or humidity. The measurements are made using closely spaced sensors arranged in a linear array on a single probe, which may be used to take measurements at multiple levels within the product. Data from the sensors is transmitted to a data collection point via short range wireless digital communications. The sensors may be used to measure temperature and humidity at a single point. For example, when the sensors are used in pharmaceutical freeze drying, the location of a sublimation front may be calculated for each vial, and the freeze drying process may be controlled using the data.