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Description
This picture shows the scatterometer winds (in arrows, flags or all ambiguities), with an infrared satellite image (from METEOSAT, GOES or Himawari) and numerical weather prediction model forecast winds from ECMWF in green arrows or flags. These model winds are valid at the time of observation. A wind flag is represented by barbs and solid pennants, a full barb representing a wind speed of 5 m/s, a half barb representing a wind speed of 2.5 m/s, and a pennant representing a wind speed of 25 m/s. A calm indicator circle is plotted if the wind speed is less than 0.5 m/s. The scatterometer winds are coloured according to the Beaufort scale, winds up to 5 Bft. (10.7 m/s) are in red, winds as of 6 Bft. are coloured as shown in the legend below the picture. A black arrow or flag indicates that the KNMI QC flag is set, such winds are likely to be unreliable but they may provide extra information to experienced users.

The ambiguity plots show up to 4 wind solutions that are input to ambiguity removal. The winds are shown as arrows without head, i.e., they point to the direction where the wind is blowing to. For the ambiguity plots a different wind speed colour scale is used. Infrared imagery and model winds are not shown in these plots. The winds having the KNMI QC flag set are coloured according to the colour scale but they are indicated with a black dot.

The exact data acquisition time is plotted in red next to the satellite swath.

The coloured dots give the value of the Maximum Likelihood Estimator (MLE) which indicates how well an observation fits to the Geophysical Model Function. High MLE values usually indicate high spatial wind variability or rain presence in the Wind Vector Cell.