Hurricanes show up clearly on radar as circular areas of moderate to high reflectivity, often surrounding a low reflectivity center.
This image shows
the reflectivity field from a scan of Hurricane Erin on August 2, 1995.
The lack of symmetry
indicates that Erin was a rather weak hurricane,
especially compared to Andrew.
The velocity field of Hurricane Erin
reveals the strong counterclockwise rotation
responsible for the inward flow on the storm's north side and the outward
flow on the south side.
Negative values (blue-green) denote movement toward the
radar and positive values (yellow-red) represent movement away from the radar.