Using satellite imagery to improve on-air forecasts and nowcasts

Geostationary Operational Environmental Satellites (GOES) provide an underutilized data source which can supplement other data, such as radar, in a forecasting and nowcasting environment. In addition to thunderstorm identification, visible satellite imagery can be used to track thunderstorm outflow boundaries, which have the potential to initiate new convection. Certain features of supercell thunderstorms, such as overshooting tops and flanking lines, are indicators of storm intensification and can be seen from GOES. Infrared (10.7 ìm) imagery can be used to identify other severe storm signatures, such as the enhanced-V. During Rapid Scan Operation (RSO), 8 satellite images are available per hour, rather than the routine 4. This increased temporal resolution can greatly improve nowcasts. In addition, the underutilized GOES shortwave infrared channel (3.9 ìm) can be used to differentiate between snow and fog, and it may provide information about thunderstorm updraft strength by measuring cloud-top albedo.

This presentation will build on the examples shown at last year's Broadcaster's Conference in New Orleans. Severe weather events from the 2005 storm season will be analyzed. Finally, examples showing the usefulness of the shortwave infrared channel will be presented.