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Regional Outbreaks of Severe Weather Through Early Next Week; Early Season Heat Wave across the South

Active spring pattern across the center of our nation with several episodes of severe weather and heavy rainfall expected into next week. The potential for very large hail, long track tornadoes, severe wind gusts, frequent cloud to ground lightning strikes and flash flooding are in the outlook. Furthermore, dangerous early season heat wave continues for the Gulf Coast states into early next week. Read More >

Upper-air Observations Program

 

Map of North America showing current status of station

Upper-Air Operational Level Status as of 05/05/2025

 

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).

 

Related Links


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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