This question is asked to me more often than you think.
The big one is what is that Imagery you use in the video updates that shows the winds over water and how does it work? Its a legit question and sometimes I myself am a little confused by the whole process. So lets start off by reading the following blurb from the Center of Satellite research and Applications.
"Satellite-based sensors are capable of systematically providing measurements over the entire globe. Sensors operating at microwave frequencies can make measurements of the ocean surface day and night and under nearly all-weather conditions.Both active (radar) and passive (radiometer) microwave sensors have been shown capable of retrieving the ocean surface wind speed, with active microwave instruments being used to also retrieve the wind direction. With the Navy's WindSat mission, a space-based radiometer system has also been shown capable of determining the wind direction using polarimetric and multi-look observations. However, the presence of significant cloud liquid water presents significant challenges for the passive polarimetric technique and thus limits its utility in supporting operational marine weather forecasting and warning. The development and refinement of instrumentation and algorithms for ocean surface wind retrieval is an ongoing process being conducted in both the active and passive remote sensing areas."
Now lets put it in a language most can understand, this product can only work over water as it sends radar beens off of wave action in the ocean. By doing this it can tell what direction waves are moving and how fast thus being able to retrieve an approximate wind speed and direction. An invaluable tool that has progressed tropical meteorology beyond a few surface plots gathered by ships in the Ocean and isolated islands.
There are a few limitations to this amazing product, for starters the most obvious, it can only work over water. So for anyone looking to find information in remote areas of siberia using this product you will not run in to much luck.
Another is that it is derived from a polar orbiting satellite vice a geo stationary, what this means is only 2 images a day can be taken of a specific area and sometimes those images may even had data gaps in them if the satellite does not go directly over the area one so desires.
Lastly is the top end of the winds, the product is only good up to about 50kts, after that wave action becomes to disturbed to successfully be read. Therefore it is a useful product in determining the strength of weak systems, but anything large than a moderate tropical storm one would need more information.
With all that said this product reigns one of the best in my book and thats why I took the time to explain it.
Find a few of the products here