Use the Wind Chart to see prevailing weather systems forecast at the flight's estimated time of departure (ETD).
How the Chart is Created
The Wind Chart displays a snapshot of the weather at the flight’s ETD over a map of the entire route. When reading the chart, keep in mind that the winds, temperatures, and turbulence depicted on it are accurate at the moment an aircraft takes off, but increasingly outdated the longer the flight progresses.
NOTE: To see how the weather will look at each point in time along the flight, refer to the Vertical Cross Section Chart.
The Wind Chart from the HTML briefing and the Wind/Temp/Turb Chart from the PDF briefing are nearly identical, and contain the following elements:
En Route Altitude - The en route altitude is listed as a flight level (FL).
Valid Time - The flight's ETD, and the time at which the weather forecast displayed over the whole chart is valid. On the PDF briefing, this field is labeled "Time".
Data Source - Each chart lists information about the data source and the date and time when the weather data was reported.
Latitude - Latitude values are added along the left and right borders of the chart.
Longitude - Longitude values are added along the top and bottom borders of the chart.
Wind Barbs - Wind barbs indicate the wind direction based on the forecast at the estimated time of departure. The barbed end is the “from” end, and the dotted end is the “to” end. The barbed end indicates wind speed as follows:
- An absence of barbs indicates calm winds.
- Short barbs indicate 5 knots of wind.
- Tall barbs indicate 10 knots of wind.
- Triangular (or pennants) barbs indicate 50 knots.
Add the sum of the values represented by the barb symbols to determine the wind speed.
Temperature - The temperature is displayed as negative degrees Celsius unless a plus sign (+) is noted next to the temperature value. The temperature is based on the forecast at the estimated time of departure.
Sample Wind chart seen in a Graphical (HTML) flight briefing
The PDF briefing adds turbulence information on the map. The turbulence EDR scale is at the bottom of the flight and forecast information box.
Sample Wind/Temp/Turb chart seen in a PDF flight briefing