dropsonde

thumb|Dropsonde delivery system on a NOAA P-3 Hurricane Hunter. A dropsonde is an expendable weather reconnaissance device created by the National Center for Atmospheric Research (NCAR), designed to be dropped from an aircraft at altitude over water to measure (and therefore track) storm conditions as the device falls to the surface. The sonde contains a GPS receiver, along with pressure, temperature, and humidity (PTH) sensors to capture atmospheric profiles and thermodynamic data. It typically relays this data to a computer in the aircraft by radio transmission.

== Usage == thumb|upright=1.25|A diagram of an NCAR GPS dropsonde Dropsonde instruments are typically the only current method to measure the winds and barometric pressure through the atmosphere and down to the sea surface within the core of tropical cyclones far from land-based weather radar. The data obtained is usually fed via radio into supercomputers for numerical weather prediction, enabling forecasters to better predict the effects and intensity, based on computer-generated models using data gathered from previous storms under similar conditions. This helps meteorologists to more reliably establish a storm's potential damage, based on those factors.