Meteorological Service of Canada Weather Alert Dissemination Challenges

The Meteorological Service of Canada (MSC) communicates hazardous weather event information and public risk information (for hurricanes, tornadoes, winter storms, etc), through its public alerting service. The Common Alerting Protocol (CAP), is one vehicle used to communicate information about these threats to agents along the path of distribution, which in turn, distribute this information to interested and affected audiences. Information included in MSC alerting service include impacted locations, applicable time-periods, measures of urgency, severity, and confidence, and much more. Downstream dissemination systems utilize this information to build presentations that notify audiences of the elevated risk of weather-driven impacts to life and property. These dissemination channels include mobile wireless networks, television/radio networks, as well as internet platforms. These systems and channels ensure that once MSC builds a public alert, it is communicated in a timely and effective way to all audiences.

With an effort to modernize the production and delivery of convective warnings in Canada, the MSC’s Convective Alert Modernization (CAM) project aims to reduce the areal over-alerting of tornado and thunderstorm warnings by introducing free-form polygons that more precisely represent the boundaries of convective hazard risks. The inclusion of greater areal and temporal precision, however, highlights challenges related to the management of warnings that can be more frequently updated, as the threat area moves in space and time.

This presentation will highlight some key dissemination challenges, pertaining to over-alerting in space, time, or message frequency, as well as the CAM project improvements planned to address these dissemination concerns.