Dropsondes, or dropwindsondes, are in situ instruments designed to be released from aircraft. Dropwinsonde are fitted with Global Positioning System (GPS) receivers to measure the atmospheric state parameters (temp, humidity, windspeed/direction pressure) and location once every half-second in 3D space during the sonde's descent. Measurements are transmitted to the aircraft from the time of release until impact with the ocean's surface.
Delivery of Suomi National Polar-orbiting Partnership (Suomi NPP) satellite data products will cease on November 1, 2026. Data users should transition now to alternative products from NOAA-21 and NOAA-20.
Suomi NPP data announcement