Expanded Cloud Base and Backscatter Detection Using the ASOS Ceilometer

The National Weather Service (NWS) Automated Surface and Observing System (ASOS) currently provides cloud base height reports up to 12,000 ft above ground level (AGL). The Vaisala model CL31 ceilometer used by ASOS has the capacity to report cloud bases up to 25,000 ft AGL. To investigate the potential benefit of adding cloud base reports from 12,000 to 25,000 ft AGL, the NWS and the University of Maryland Baltimore County conducted a 3-phased research study at several geographically-diverse locations across the United States. ASOS ceilometer data above 12,000 ft AGL was validated against co-located lidars. This poster will describe the results from the research study and the potential benefits of the additional cloud base and aerosol backscatter profile data. Applications of the additional data include improved detection of frontal passages, bay/sea breezes, and volcanic ash, the transport of atmospheric pollutants, and infusion of middle and high cloud data into numerical prediction models.