A sequence of GOES images, separated by 15 or 30 minutes, are used to compute winds from satellite images. Satellite meteorologists are able to generate winds at different levels of the atmosphere all around the globe.
This is particularly useful over the oceans where conventional weather observations are not possible. While it's true that buoys and ships send in weather observations they simply can't contribute anywhere near the coverage offered by satellites.

The accuracy of weather forecasts improved dramatically during the 1990's due to the addition of satellite derived winds in forecast models. This has been especially crucial to the timing and location of where a hurricane makes landfall.