Enhancing Weather Observations: Bridging the Gap Between Airborne Measurements and ASOS Data

Automated Surface Observing System (ASOS) stations are widely distributed across the United States, providing local current weather conditions like temperature and precipitation. Despite their many capabilities, there are challenges in accurately capturing spatial variability with them, and thus variation in cloud and precipitation is missed by them. This research compares airborne data collected during the NASA Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Snowstorms (IMPACTS) field campaign with the ground based ASOS observations to assess the representativeness of the ASOS data. Vertical profiles of radar reflectivity from the Ka-band High Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP) along the ER-2 flight tracks for all flights conducted in 2020, 2022, and 2023 are generated and compared to the ASOS data. The comparison of the HIWRAP data and the ASOS data determines the consistency between the upper-level precipitation pattern and the measured intensity at the ground. The findings reveal that the ASOS stations do not capture variability shown by the HIWRAP, especially for times that the ASOS measures higher precipitation. Furthermore, in cases where the ASOS station observes lower precipitation intensities, inconsistencies are found between the radar reflectivity and the ASOS station readings. Specifically, the radar reflectivity often shows higher intensities compared to the ASOS observations. This presentation delves into sensitivities on how the averaging period of the data sets affects the ASOS/HIWRAP comparison to determine the degree to which the ASOS can characterize precipitation in winter storms.