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Four years (April 2014 to March 2018) of Global Precipitation Measurement (GPM) Precipitation Features data along with colocated the Modern Era Retrospective‐Analysis for Research and Applications‐2 model data are used to identify Freezing Rain Features (FRFs). A Precipitation Feature with presence of both melting layer (maximum temperature of the vertical column > 4 °C) and a layer of subfreezing air (2‐m temperature < 0 °C) adjacent to the surface is considered an FRF. During 4 years of observations, GPM and Modern Era Retrospective‐Analysis for Research and Applications‐2 identify approximately 3,096 FRFs globally (65°S–65°N). Most of them are observed over Northern Hemispheric land in the winter season. The majority of FRFs originates through the “melting process,” whereas only 35 features are associated with “warm rain” process. The locations and seasonal and diurnal distribution patterns of the FRFs over the United States are well matched with the ground‐based observations. The ground‐based observations verify approximately 70% of the FRFs over the United States. Ku‐band radar properties show that FRFs are found shallower (2–5 km) and less intense (<27 dBZ) than precipitation features in general but deeper and more intense than Snow Features. Passive microwave properties show that FRFs Tbs and Polarization‐Corrected Temperature are warmer than Snow Features at all GPM Microwave Imager channels with the largest differences in 166 GHz. The enhancement in Tbs are more distinct with warm rain FRFs. FRF Tb tends to decrease as echo top height increases at all GPM Microwave Imager channels except for 183 GHz, where Tbs have lack of dependence on echo top height. GPM Ku‐band radar and MERRA‐2 reanalysis data are used to identify Freezing Rain eventsRadar and Passive microwave properties of freezing rain events are summarizedPassive microwave properties show that FRFs Tbs and PCTs are warmer than SFs at all GMI channels

Six‐years (2010–2015) of snow lightningcharacteristics and climatology, including seasonal, diurnal, and surface temperature distribution, are generated. The World Wide Lightning Location Network (WWLLN) and the National Lightning Detection Network lightning observations are collocated with Modern‐Era Retrospective Analysis for Research and Application (MERRA‐2) temperatures. Cold season lightning events are identified as lightning with the MERRA‐2 two‐meter surface temperature colder than 0 °C and then further classified as snow lightningor thundersnow, when the entire vertical temperature profile is below 2 °C, and as freezing rain lightning when there is a temperature warmer than 2 °C somewhere in the column above the freezing surface. The statistics of snow lightning events from WWLLN and National Lightning Detection Network are well matched and are consistent with the climatology of thundersnow days reported at ground‐based stations over the United States. Using 4 years of observations from the Global Precipitation Measuring Mission Ku band radar, 443 Thunder Snow Features (TSFs) are defined, having a contiguous area of nonzero near surface snow precipitation derived from the Ku band radar and MERRA‐2 data, along with collocated WWLLN lightning flashes. The majority (about 394) are found over high mountainous regions such the Himalayas, Tibet, the Andes, and the Zagros mountain regions. Low‐elevation TSFs (45) are observed over the continental and coastal regions. Though only a small number of TSFs are identified with 4 years of Global Precipitation Mission data, most TSFs have maximum radar reflectivity above 30 dBZ at temperature colder than −10 °C, which indicates the importance of the noninductive charging process in these events. Snow lightning characteristics and climatology are generated over the United StatesThe geographical distributions of thundersnow systems observed by the GPM satellite are mapped globallyThe Ku band radar characteristics of global thundersnow snow features are summarized