The Center Weather Advisory is aimed at informing aircraft staff about certain concerning conditions. As a rule, air crews refer to it as a means of predicting and escaping negative weather conditions, such as turbulence and icing (AVC, n.d.). This product’s predictions may only be used in the span of 2 hours. Thus, it is quite a short-term forecast product that is not reliable upon surpassing this specific time period.
AIRMET’s goal is to inform flight staff of current or future phenomena that can negatively influence the safety of aircraft operations. This service may be used if they were not previously mentioned in a Graphic Area Forecast (NavCanada, n. d.). The second condition for the use of AIRMET involves the location and time. Thus, the service’s limit is focused on whether certain conditions were mentioned previously or not.
SIGMET is a message reported by a meteorological watch office. The service’s goal is identical to the aim of AIRMET, as it usually reports dangerous conditions (NavCanada, n. d.). Moreover, this message reports about the location and the time of the development of those conditions. Additionally, it is used for a vast number of various natural phenomena. Thus, the service’s limit is defined by certain conditions and their definitive features.
In conclusion, three weather forecast services were reviewed: SIGMET, AIRMET and CVA. To summarize, all three services inform the staff of the current or upcoming phenomena that may negatively affect the safety of aircraft operations. However, the differences are defined by the limits of each service, which include time, specific phenomena and prior documentation. Thus, it is significantly easier to differentiate between the three weather forecast services.
References
Aviation Weather Center, NOAA National Weather Service (n.d.) Center Weather Advisory (CWA), CWA/MIS Help.
NavCanada (n.d.) Aviation Weather Services Guide for Aviation Users. pp.1-50. NavCanada.