The “U-Tube”: An improved aspirated temperature system for mobile meteorological observations, especially in severe weather

Abstract

AbstractObtaining quality air temperature measurements in complex mesoscale environments, such as thunderstorms or frontal zones, is problematic, and particularly challenging from a moving platform. For some time mobile weather platforms known as Mobile Mesonets (MMs) have used custom aspirated temperature shields. The original design was known as the “J-Tube”, which addresses some but not all of the unique problems associated with mobile temperature measurements. For VORTEX-2 2009, a second, well documented shield, the R.M. Young (RMY) 43408 was included but was also found to have certain shortcomings in some severe weather environments. Between the end of VORTEX2 2009 and the start of VORTEX2 2010, a third and new shield called the “U-tube” was designed, tested and installed.Reported here are the results of efforts to better characterize the J-Tube, RMY 43408, and the U-Tube. Several tests designed to isolate key aspects of a radiation shield’s performance, such as performance in rain, high solar radiation, varying wind conditions, and general response time were completed. A period of intercomparison between the three shields during the 2010 season of VORTEX 2 is also used to highlight each shield being used in “real world” conditions. Results indicate that the U-Tube has several significant advantages over the J-tube and 43408 in terms of aspiration rate, sampling efficiency, performance during rain, variable winds, and high solar radiation periods, as well as response time. Given these results, the U-tube should be utilized for mobile observations going forward.