Rawinsonde (RAOB) Data Archive

For many moons, the IEM archived the soundings provided by the now defunct NOAA rucsoundings website. This website was shutdown during September 2024, so the IEM started to ingest what was provided by the Storm Prediction Center website. This source was found to be missing many sounding locations that the IEM previous archived. So the IEM started to ingest what is provided by NCEI Integrated Global Radiosonde Archive, but this archive is not in real-time. So as of March 2025, this website contains near real-time data from SPC and is backfilled eventually with data from the NCEI archive.

Data for the United States and Canada is available. This data are vertical profiles of the atmosphere taken from weather balloons released twice daily.

Available Tools:

Download Data

This form provides a simple comma delimited file of RAOB data, the columns should be self-explainatory except the 'levelcode' column. Those values provide metadata on that level of data. The start time is inclusive and end time is exclusive. Special soundings should be in this archive as well.

Level Codes
  • 4 = mandatory level
  • 5 = significant level
  • 6 = wind level (PPBB)
  • 7 = tropopause level
  • 8 = maximum wind level
  • 9 = surface level
 Output Datafile Columns 
station      3 or 4 character station identifier
validUTC     RAOB Launch Cycle Time in UTC
levelcode    Level Code for this observation, not always available
pressure_mb  Pressure of data in millibar
height_m     Height above sea level m
tmpc         Air Temperature in C
dwpc         Dew Point Temperature in C
drct         Wind Direction in deg from North
speed_kts    Wind Speed in knots
bearing      Balloon bearing in degree, not always available
range_sm     Ballon range from launch in statute miles, not always available
Select Site: Start Time: End Time:

JSON(P) Webservice

A JSON webservice exists for more programatic access, more information is here.