For the identity of these coded stations, or a complete listing of all possible reporting stations for upper air data, go to Listing of Upper Air Weather Stations.

The diagram below shows the legend for interpreting the data for each station as displayed in a station model on upper atmospheric constant pressure maps. The complete explanation is given at the right for the station model example shown.

Temp (C) Dewpoint (C)

Height (m) Wind (kts)

Data at Pressure Level Temp -5 °C, dewpoint -12 °C, wind from S at 75 knots, height of level 1564 m

On these maps, altitude at which the chosen pressure occurs are given in meters, coded to conserve space on the map. One needs to add one or more digits to decode the actual altitude from the station model.

Upper air charts are typically drawn for "surfaces"of constant pressure, that is, assembled from data collected twice daily by rawinsondes at that particular pressure value. The routine pressure values for which upper air maps are displayed by the DataStreme Atmosphere homepage are: 850 mb, 700 mb, 500 mb, 300 mb. Additional data are collected including so-called mandatory levels from each rawinsonde measurement profile (if sufficient altitude is achieved): 1000, 925, 850, 700, 500, 400, 300, 250, 200, 150, 100, 85, 70, 50, 40, 30, 25, 20, 15, 10 mb.