Here is a picture for comparison (from => http://www.goes.noaa.gov/HURRLOOPS/huirloop.html).
The image above is from a satellite, Hurricane Infrared: GOES East. Notice just how big Irma is compared to the other two storms that are currently out in the Atlantic.
This chart shows the probable path of the storm (from => http://www.nhc.noaa.gov/graphics_at1.shtml?cone#contents). Irma will engulf the Florida peninsula.Note the maximum sustained wind and the huge size of the wind field shown in the graphic above. The storm surge, that is the water the storm drags ashore will be extensive, and that flooding will probably cause the most damage. It is the wind speed and the size of the storm that determines the extent of shore line that experiences the storm surge. In addition, the wind speed and the size of the storm helps to determine how long the high winds and the heavy rains (more flooding) lasts.
If you want of understand the importance of the wind speed, check out this website and carefully consider the graphic: Saffir-Simpson Hurricane Wind Scale.