Cloud lightning performance and climatology of the U.S. based on the upgraded U.S. National Lightning Detection Network

The 2013 upgrade of the U.S. National Lightning Detection Network (NLDN) was anticipated to provide uniform cloud lightning (IC) flash detection efficiency (DE) of about 50% over the entire continental U.S. Preliminary validation of the cloud lightning performance using Lightning Mapping Array (LMA) data from Kansas and Colorado showed that this expectation was generally met during late summer and fall, 2013, albeit with some variability. In this study, we expand upon the preliminary work by adding additional LMA data and additional case studies during 2014 to verify that the upgraded NLDN continues to meet the expected level of IC lightning performance. Further, we utilize the first full year of data from the upgraded NLDN to offer the first IC-only lightning climatology of the continental U.S. We also provide an NLDN-based version of the climatology of the IC-CG ratio over the U.S., an initial version of which was published in 2000 based on comparisons of NLDN data with the low-earth orbiting satellites OTD and LIS (Optical Transient Detector and Lightning Imaging Sensor).