Testing the Radiosonde Replacement System (RRS) Radiosondes in a Maritime Polar Environment

The National Weather Service (NWS) has completed pre-production testing of the Sippican Mark IIA radiosonde for use in their upper air network. Over the course of evaluating this radiosonde during the pre-production tests, additional problems were identified. Sippican implemented changes in their production process, their humidity duct design and temperature boom positioning procedures to correct design flaws. To insure the radiosondes perform correctly over the range of weather condition encountered at the NWS upper sites, the NWS would normally conduct a test spanning at least three seasons. To expedite this process, the NWS selected four different sites to evaluate the radiosonde including: Caribou, Maine, San Diego, California, Sterling, Virginia, and Quillayute, Washington. This paper covers the testing at the Quillayute upper air site. Quillayute was selected to evaluate the radiosonde in the maritime polar air mass usually dominating the weather over the coastal areas of the Pacific Northwest during the winter months. Conditions expected for the test were cool temperatures with overcast low clouds and rain. This paper will provide some preliminary results from testing in this environment.