Huaqing Cai

Convection diagnosis and nowcasting for oceanic aviation applications

An oceanic convection diagnosis and nowcasting system is described whose domain of interest is the region between the southern continental United States and the northern extent of South America. In this system, geostationary satellite imagery are used to define the locations of deep convective clouds through the weighted combination of three independent algorithms. The resultant output, called the Convective Diagnosis Oceanic (CDO) product, is independently validated against space-borne radar and lighting products from the Tropical Rainfall Measuring Mission (TRMM) satellite to ascertain the ability of the CDO to discriminate hazardous convection. The CDO performed well in this preliminary investigation with some limitations noted. Short-term, 1-hr and 2-hr nowcasts of convection location are performed within the Convective Nowcasting Oceanic (CNO) system using a storm tracker. The CNO was found to have good statistical performance at extrapolating existing storm positions. Current work includes the development and implementation of additional atmospheric features for nowcasting convection initiation and to improve nowcasting of mature convection evolution.

Brightness temperature nowcasting for satellite-based short-term prediction of storms: opportunities and challenges

Satellite-based brightness temperature observations are used in a wide range of applications for monitoring weather systems over land and especially over water, including short-term prediction of the evolution of weather systems. Results are presented from an evaluation of three extrapolation-based nowcasting procedures to predict satellitebased brightness temperatures up to 3 hours into the future. Analyses are based on using METEOSAT-8 Spinning Enhanced Visible and Infrared Imager (SEVIRI) data as a proxy for the Advanced Baseline Imager (ABI) to be flown on the next-generation National Oceanic and Atmospheric Administration (NOAA) Geostationary Operational Environmental Satellite (GOES)-R series.