Record the results. You can do this for each of the designated velocities. Compare and measure the impact of wind velocities before the storm makes land fall with image 9510041612 and the image you just analyzed. There is a 4 hour and 35 minutes time difference between the two images. Depending upon the area you want to measure, you can always reset the minimum and maximum particle sizes.
Particle size refers to the number of pixels being measured.
When working with satellite images, measurements are not entirely accurate. On these types of images, pixel vaules representing distances have different values directly below the satellite as opposed to those located on the edge of the image.