Decoding Guide

Winds and Temperatures Aloft


This product depicts the observed winds and temperatures at various altitudes for reporting stations across the U.S. These observations are obtained daily at 00Z and 12Z from weather balloon releases. Observations are made at various pressure levels which approximately correspond to the altitude indicated on the chart. Since the measurements are made by pressure level instead of altitude, it is important to note that the altitude is an approximation only and will vary measurement-to-measurement and reporting station-to-reporting station.


0000 and 1200 UTC

Data Sources:

Radiosonde-equipped weather balloons


A wind barb is used to indicate wind speed and direction. Yellow text next to the barb gives the station identifier and the temperature in degrees F.


Winds Aloft

This example shows an observation made at station OAX (Omaha Nebraska) with 20 knot winds observed from approx 260 degrees. The temperature at this (apparently high) altitude is -84 degrees F.
Click Here for a Discussion on Wind Barb Notation