Forecasting and nowcasting improvement in cloudy regions with high temporal GOES sounder infrared radiance measurements

Abstract

[1] In an effort to extend the high temporal resolution Geostationary Operational Environmental Satellite (GOES) infrared sounding retrievals from clear to cloudy skies, a synthetic regression-based cloudy sounding retrieval algorithm has been developed and applied to GOES 12 sounder measurements. Comparisons against radiosondes at the Atmospheric Radiation Measurement Program at Southern Great Plains site from August 2006 to May 2007 and the conventional radiosondes network over the continental United States from January 2007 to November 2008 both show that the retrievals of moisture under thin cloud conditions perform similarly to those under the clear-sky conditions. The largest improvements are found in the upper level integrated precipitable water vapor (PW) or PW3. Also in the case of low thick clouds, PW3 is usually improved significantly. In addition, the retrieved cloud parameters are consistent with the false RGB composite images. With the addition of the soundings under low thick or thin cloud conditions, the area without soundings is reduced by 57% in the selected case. The application to a tornadic storm on 24 April 2007 reveals that the GOES cloudy sounding retrievals are more useful at the early stage of the storm, when nearby clouds are considered thin or broken. The GOES cloudy sounding algorithm reveals more pronounced and extensive convective instability, and it does so earlier than the clear-sky-only results. The cloudy sounding retrievals have the potential to provide an earlier warning to forecasters. Copyright 2009 by the American Geophysical Union.