The Winds and Temperatures Aloft Forecast (FD) gives an estimate of wind direction as it relates to true north, the wind speed (in knots) and the temperature (degrees Celsius) for selected levels of altitude.

A sample Winds and Temperatures Aloft Forecast (FD) is shown below.

FD	KSJC	161640
DATA BASED ON 161200Z
VALID 16180Z FOR USE 1700 -2100Z TEMPS NEG ABV 24000

FT	3000	6000	9000	12000	18000	24000

HOU	2619	2728+01	2635-05	2641-09	2654-21 2665-32
JOT	2526	2736+01	2642-06	2649-11	2662-22	2674-33

Line1
Winds and Temperature Aloft (FD), San Jose International Airport, CA, 16th day of month, time: 1640.

Line2
States that the forecast is based on observations made on the 16th day of the month at 1200 Zulu time.

Line3
Report is valid on the 16th day of the month at 1800 Zulu time and is to be used from 1700 - 2100 Zulu time. Temperatures above 24,000 feet are always negative, this note indicates that the negative sign (-) is not shown on numbers for 30,000 feet and above.

Line 4
This line contains the column headings for the information now shown in chart form. Each column indicates the altitude at which the winds and temperatures were measured. These are recorded in feet (FT) beginning with 3,000 and as this is a partial chart only going up to 24,000 feet.

Line5
Location identification code (HOU) for Houston, Texas. The next group of 6 numbers is broken up by pairs. The first 2 digits (26) give the true direction from which the wind is blowing which is 260 degrees. The second pair of digits (19) gives the wind speed in knots (19 knots). The third pair of numbers indicate the temperature, however temperatures are not reported for 3,000 feet and less. So, going to the second group of numbers (2728-01) the information tells us that at 6,000 feet the winds are from 270 degrees with a windspeed of 28 knots and a temperature of 1 degree C.

Line 6
This line contains information for Joliet, IL (JOT) and is read the same as above.