Scattered severe thunderstorms capable of large hail in excess of two inches, strong tornadoes, and damaging wind gusts are likely across parts of the Upper Mississippi Valley and Midwest this evening. Heavy to excessive rainfall may bring a flooding threat to portions of the Central Plains to the Midwest through Thursday. The heatwave in the Central U.S. will begin to push South and East Thursday Read More >
The National Weather Service (NWS) Upper-air Observations Program is managed by the Office of Observations (OBS), which is part of NWS Headquarters located in Silver Spring, Maryland. Upper-air Program staff oversee the operation of 92 Radiosonde stations in North America and the Pacific Islands. While also supporting the operation of 10 stations in the Caribbean, a Cooperative Program known as the Cooperative Hurricane Upper Air Stations (CHUAS). Radiosondes provide upper-air data that are essential for weather forecasts, research, and historical climatology, and are launched twice daily at (00z and 12z), with additional SPECI releases supporting critical weather at 06z and 18z, or as needed. OBS staff are also involved in the development, testing and implementation of new radiosonde ground systems, as well as any part of the balloon flight train that brings the radiosonde into the atmosphere. This can include cotton twine, parachute, balloon and dereeler/unwinder. In the event of any issues during flights, the Sterling Field Support Center Upper Air Help Desk was created to offer assistance 16 hours a day, seven days a week, to mitigate loss of data (https://www.weather.gov/soic/field_support).
Fact Sheet- Information on radiosondes.
Network Maps - Maps showing station locations..
Special Studies - NWS HQ radiosonde data studies.
Background - History of upper-air observations.
FAQ - Frequently Asked Questions.
NCEI - NOAA/National Centers for Environmental Information. Official source for archives of NWS upper air soundings.
NWSM 10-1402 Radiosonde Observations Handbook This manual provides procedures for upper air launch sites operationally using the AROS or MROS system.
Upper-air Sites Ground Equipment and Radiosonde Types
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