Telemetry of Observed Total Accumulated Liquid (TOTAL) Precipitation Trailer Introduction and Preliminary Results

There are several limitations with accurately measuring the amount of liquid precipitation that occurs during a weather event. The liquid-equivalent and total liquid accumulation of solid and liquid precipitation is typically conducted through radar estimates and gauge observations; however, there are challenges with these datasets, especially with gauge observations that are used as ground truth and eventual bias corrections. NOAA National Severe Storms Lab (NSSL) and University of Oklahoma (OU) - Cooperative Institute for Severe and High-Impact Weather Research and Operations (CIWRO) have developed a new mobile instrumentation platform designed to improve precipitation measurement accuracy in all types of precipitation and identify areas of bias and error. Many research questions are to be examined in the coming years with the TOTAL trailer such as true liquid content of frozen precipitation, wind undercatch in both frozen and liquid precipitation, verification and improvement of Quantitative Precipitation Estimations (QPE), and many more.

The operational strategy of the TOTAL trailer includes collocating observations near a fixed or mobile radar for concurrent observations for comparison. Other sites that have been identified for potential use have duplicate surface observations for trailer comparison and analysis. Current operational instrumentation available on the TOTAL trailer are a mobile mesonet rack, heated tipping bucket, heated weighing gauge, CoCoRaHS gauge, Parsivel laser optical Disdrometer, FD-70 forward scattering sensor, 24-GHz Doppler radar precipitation sensor, hotplate precipitation gauge, infrasonic detector, electric field mill, and all-sky 360-degree camera. Initial testing has begun with the TOTAL trailer on site at NSSL and evaluation is ongoing with the data captured. Extended test deployments are planned to evaluate the full capabilities and limitations of the trailer. Future plans for the trailer include consistent data collection in and around Oklahoma for any mode of precipitation as well as collaborative, targeted field campaigns to answer specific scientific questions.