Profiler/Radiosonde

Wind Profilers, another type of Doppler Radar, point vertically and also provide information about the change in wind speed and direction above the radar site. A network of Wind Profilers is being installed across the Nation in order to allow forecasters to track “small-scale” weather disturbances that increase the chances for severe thunderstorm development. The Wind Profilers will also provide information that leads to improved forecasts of other types of dangerous weather, such as winter storms, and will provide useful information to aviation weather forecasters. Radiosondes are meteorological instruments attached to balloons that are launched twice daily, at 1200 and 0000 Universal Coordinated Time (UTC). These instruments relay information concerning the change of temperature, moisture, and wind with increasing height. One necessary condition for thunderstorm development is that the rising air within a thunderstorm updraft remain warmer than the surrounding air. Such a condition is known as “instability”. Information from radiosondes can be analyzed and atmospheric instability assessed, providing dues to thunderstorm potential. Photo of Wind Profiler system and output (left and center, respectively) and radiosonde balloon launch (right). (NOAA/NWS)