James F. W. Purdom
Nowcasting, K. Browning, Ed., Academic Press, 149-166
Nowcasting and the very-short-range forecasting of mesoscale weather is one of the most challenging problems in meteorology today. There are a variety of reasons for this, not the least of which is that the mesoscale remains ill-defined and poorly understood. For that reason, immediate improvements are most likely to be achieved through the incorporation of empirical information into new procedures for nowcasting various meteorological situations. This is no trivial task. Such an approach requires immediate display capability for current data (satellite, radar, surface mesonets, etc.), provision for their combination, and the availability of products derived from those data in a readily comprehensible form for the meteorologist involved in the decision-making process. This is one of the major goals of the PROFS program (elsewhere in this volume, or Beran, 1980). The broader problem is the investigation of how satellite and other data sets can be combined and analyzed to gain a better understanding of mesoscale atmospheric processes. Satellite data and their use for nowcasting and very-short-term forecasting, with particular emphasis on convection, is the major topic to be discussed in this chapter.
Geostationary satellite data is likely to become one of the major footings upon which mesocsale forecasting programs of the future are based. By combining satellite data with more conventional data, such as radar and surface observations, many of the features important in mesoscale weather development and evolution may be better analyzed and understood. This better analysis and understanding of mesoscale processes is necessary if very-short-range forecasting is to be sucessful.